Commit Graph

638 Commits

Author SHA1 Message Date
Nadav Har'El
e0693f19d0 alternator test: produce newer xunit format for test results
test.py passes the "--junit-xml" option to test/alternator/run, which passes
this option to pytest to get an xunit-format summary of the test results.
However, unfortunately until very recent versions (which aren't yet in Linux
distributions), pytest defaulted to a non-standard xunit format which tools
like Jenkins couldn't properly parse. The more standard format can be chosen
by passing the option "-o junit_family=xunit2", so this is what we do in
this patch.

Fixes #6767 (hopefully).

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200719203414.985340-1-nyh@scylladb.com>
2020-07-20 09:24:50 +03:00
Avi Kivity
5371be71e9 Merge "Reduce fanout of some mutation-related headers" from Pavel E
"
The set's goal is to reduce the indirect fanout of 3 headers only,
but likely affects more. The measured improvement rates are

flat_mutation_reader.hh: -80%
mutation.hh            : -70%
mutation_partition.hh  : -20%

tests: dev-build, 'checkheaders' for changed headers (the tree-wide
       fails on master)
"

* 'br-debloat-mutation-headers' of https://github.com/xemul/scylla:
  headers:: Remove flat_mutation_reader.hh from several other headers
  migration_manager: Remove db/schema_tables.hh inclustion into header
  storage_proxy: Remove frozen_mutation.hh inclustion
  storage_proxy: Move paxos/*.hh inclusions from .hh to .cc
  storage_proxy: Move hint_wrapper from .hh to .cc
  headers: Remove mutation.hh from trace_state.hh
2020-07-19 19:47:59 +03:00
Rafael Ávila de Espíndola
9fd2682bfd restrictions_test: Fix use after return
The query_options constructor captures a reference to the cql_config.

Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Message-Id: <20200718013221.640926-1-espindola@scylladb.com>
2020-07-19 15:44:38 +03:00
Pavel Emelyanov
8618a02815 migration_manager: Remove db/schema_tables.hh inclustion into header
The schema_tables.hh -> migration_manager.hh couple seems to work as one
of "single header for everyhing" creating big blot for many seemingly
unrelated .hh's.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-17 17:54:43 +03:00
Nadav Har'El
3b5122fd04 alternator test: fix warning message in test_streams.py
In test_streams.py, we had the line:
  assert desc['StreamDescription'].get('StreamLabel')

In Alternator, the 'StreamLabel' attribute is missing, which the author of
this test probably thought would cause this test to fail (which is expected,
the test is marked with "xfail"). However, my version of pytest actually
doesn't like that assert is given a value instead of a comparison, and we
get the warning message:

  PytestAssertRewriteWarning: asserting the value None, please use "assert is None"

I think that the nicest replacement for this line is

  assert 'StreamLabel' in desc['StreamDescription']

This is very readable, "pythonic", and checks the right thing - it checks
that the JSON must include the 'StreamLabel' item, as the get() assertion
was supposed to have been doing.

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200716124621.906473-1-nyh@scylladb.com>
2020-07-17 14:36:23 +03:00
Rafael Ávila de Espíndola
66d866427d sstable_datafile_test: Use BOOST_REQUIRE_EQUAL
This only works for types that can be printed, but produces a better
error message if the check fails.

Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Reviewed-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20200716232700.521414-1-espindola@scylladb.com>
2020-07-17 11:58:58 +03:00
Avi Kivity
7bf51b8c6c Merge 'Distinguish single-column expressions in AST' from Dejan
"
Fix #6825 by explicitly distinguishing single- from multi-column expressions in AST.

Tests: unit (dev), dtest secondary_indexes_test.py (dev)
"

* dekimir-single-multiple-ast:
  cql3/restrictions: Separate AST for single column
  cql3/restrictions: Single-column helper functions
2020-07-16 16:59:14 +03:00
Pavel Solodovnikov
5ff5df1afd storage_proxy: un-hardcode force sync flag for mutate_locally(mutation) overload
Corresponding overload of `storage_proxy::mutate_locally`
was hardcoded to pass `db::commitlog::force_sync::no` to the
`database::apply`. Unhardcode it and substitute `force_sync::no`
to all existing call sites (as it were before).

`force_sync::yes` will be used later for paxos learn writes
when trying to apply mutations upgraded from an obsolete
schema version (similar to the current case when applying
locally a `frozen_mutation` stored in accepted proposal).

Tests: unit(dev)

Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200716124915.464789-1-pa.solodovnikov@scylladb.com>
2020-07-16 16:38:48 +03:00
Dejan Mircevski
0047e1e44d cql3/restrictions: Separate AST for single column
Existing AST assumes the single-column expression is a special case of
multi-column expressions, so it cannot distinguish `c=(0)` from
`(c)=(0)`.  This leads to incorrect behaviour and dtest failures.  Fix
it by separating the two cases explicitly in the AST representation.

Modify AST-creation code to create different AST for single- and
multi-column expressions.

Modify AST-consuming code to handle column_name separately from
vector<column_name>.  Drop code relying on cardinality testing to
distinguisn single-column cases.

Add a new unit test for `c=(0)`.

Fixes #6825.

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
2020-07-16 12:27:25 +02:00
Nadav Har'El
dcf9c888a2 alternator test: disable test_streams.py::test_get_records
This test usually fails, with the following error. Marking it "xfail" until
we can get to the bottom of this.

dynamodb = dynamodb.ServiceResource()
dynamodbstreams = <botocore.client.DynamoDBStreams object at 0x7fa91e72de80>

    def test_get_records(dynamodb, dynamodbstreams):
        # TODO: add tests for storage/transactionable variations and global/local index
        with create_stream_test_table(dynamodb, StreamViewType='NEW_AND_OLD_IMAGES') as table:
            arn = wait_for_active_stream(dynamodbstreams, table)

            p = 'piglet'
            c = 'ninja'
            val = 'lucifers'
            val2 = 'flowers'
>           table.put_item(Item={'p': p, 'c': c, 'a1': val, 'a2': val2})
test_streams.py:316:
...
E           botocore.exceptions.ClientError: An error occurred (Internal Server Error) when calling the PutItem operation (reached max retries: 3): Internal server error: std::runtime_error (cdc::metadata::get_stream: could not find any CDC stream (current time: 2020/07/15 17:26:36). Are we in the middle of a cluster upgrade?)

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
2020-07-16 08:24:25 +03:00
Nadav Har'El
61f52da9b1 merge: Alternator/CDC: Implement streams support
Merged pull request https://github.com/scylladb/scylla/pull/6694
by Calle Wilund:

Implementation of DynamoDB streams using Scylla CDC.

Fixes #5065

Initial, naive implementation insofar that it uses 1:1 mapping CDC stream to
DynamoDB shard. I.e. there are a lot of shards.

Includes tests verified against both local DynamoDB server and actual AWS
remote one.

Note:
Because of how data put is implemented in alternator, currently we do not
get "proper" INSERT labels for first write of data, because to CDC it looks
like an update. The test compensates for this, but actual users might not
like it.
2020-07-16 08:18:25 +03:00
Nadav Har'El
c4497bf770 alternator test: enable experimental CDC
In the script test/alternator/run, which runs Scylla for the Alternator
tests, add the "--experimental-features=cdc" option, to allow us testing
the streams API whose implementation requires the experimenal CDC feature.

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
2020-07-16 08:18:09 +03:00
Nadav Har'El
09a71ccd84 merge: cql3/restrictions: exclude NULLs from comparison in filtering
Merge pull request https://github.com/scylladb/scylla/pull/6834 by
Juliusz Stasiewicz:

NULLs used to give false positives in GT, LT, GEQ and LEQ ops performed upon
ALLOW FILTERING. That was a consequence of not distinguishing NULL from an
empty buffer.

This patch excludes NULLs on high level, preventing them from entering LHS
of any comparison, i.e. it assumes that any binary operation should return
false whenever the LHS operand is NULL (note: at the moment filters with
RHS NULL, such as ...WHERE x=NULL ALLOW FILTERING, return empty sets anyway).

Fixes #6295

* '6295-do-not-compare-nulls-v2' of github.com:jul-stas/scylla:
  filtering_test: check that NULLs do not compare to normal values
  cql3/restrictions: exclude NULLs from comparison in filtering
2020-07-15 18:32:14 +03:00
Calle Wilund
76f6fe679a alternator tests: Add streams test
Small set of positive and negative tests of streams
functionality. Verified against DynamoDB and Alternator.
2020-07-15 08:21:34 +00:00
Juliusz Stasiewicz
c25398e8cf filtering_test: check that NULLs do not compare to normal values
Tested operators are: `<` and `>`. Tests all types of NULLs except
`duration` because durations are explicitly not comparable. Values
to compare against were chosen arbitrarily.
2020-07-14 15:37:17 +02:00
Pavel Emelyanov
f8ffc31218 test: Print more sizes in memory_footprint_test
The row cache memory footprint changed after switch to B+
because we no longer have a sole cache_entry allocation, but
also the bplus::data and bplus::node. Knowing their sizes
helps analyzing the footprint changes.

Also print the size of memtable_entry that's now also stored
in B+'s data.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-14 16:30:02 +03:00
Pavel Emelyanov
174b101a49 row_cache: Switch partition tree onto B+ rails
The row_cache::partitions_type is replaced from boost::intrusive::set
to bplus::tree<Key = int64_t, T = array_trusted_bounds<cache_entry>>

Where token is used to quickly locate the partition by its token and
the internal array -- to resolve hashing conflicts.

Summary of changes in cache_entry:

- compare's goes away as the new collection needs tri-compare one which
  is provided by ring_position_comparator

- when initialized the dummy entry is added with "after_all_keys" kind,
  not "before_all_keys" as it was by default. This is to make tree
  entries sorted by token

- insertion and removing of cache_entries happens inside double_decker,
  most of the changes in row_cache.cc are about passing constructor args
  from current_allocator.construct into double_decker.empace_before()

- the _flags is extended to keep array head/tail bits. There's a room
  for it, sizeof(cache_entry) remains unchanged

The rest fits smothly into the double_decker API.

Also, as was told in the previous patch, insertion and removal _may_
invalidate iterators, but may leave them intact. However, currently
this doesn't seem to be a problem as the cache_tracker ::insert() and
::on_partition_erase do invalidate iterators unconditionally.

Later this can be otimized, as iterators are invalidated by double-decker
only in case of hash conflict, otherwise it doesn't change arrays and
B+ tree doesn't invalidate its.

tests: unit(dev), perf(dev)

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-14 16:30:02 +03:00
Pavel Emelyanov
cf1315cde5 double-decker: A combination of B+tree with array
The collection is K:V store

   bplus::tree<Key = K, Value = array_trusted_bounds<V>>

It will be used as partitions cache. The outer tree is used to
quickly map token to cache_entry, the inner array -- to resolve
(expected to be rare) hash collisions.

It also must be equipped with two comparators -- less one for
keys and full one for values. The latter is not kept on-board,
but it required on all calls.

The core API consists of just 2 calls

- Heterogenuous lower_bound(search_key) -> iterator : finds the
  element that's greater or equal to the provided search key

  Other than the iterator the call returns a "hint" object
  that helps the next call.

- emplace_before(iterator, key, hint, ...) : the call construct
  the element right before the given iterator. The key and hint
  are needed for more optimal algo, but strictly speaking not
  required.

  Adding an entry to the double_decker may result in growing the
  node's array. Here to B+ iterator's .reconstruct() method
  comes into play. The new array is created, old elements are
  moved onto it, then the fresh node replaces the old one.

// TODO: Ideally this should be turned into the
// template <typename OuterCollection, typename InnerCollection>
// but for now the double_decker still has some intimate knowledge
// about what outer and inner collections are.

Insertion into this collection _may_ invalidate iterators, but
may leave intact. Invalidation only happens in case of hashing
conflict, which can be clearly seen from the hint object, so
there's a good room for improvement.

The main usage by row_cache (the find_or_create_entry) looks like

   cache_entry find_or_create_entry() {
       bound_hint hint;

       it = lower_bound(decorated_key, &hint);
       if (!hint.found) {
           it = emplace_before(it, decorated_key.token(), hint,
                                 <constructor args>)
       }
       return *it;
  }

Now the hint. It contains 3 booleans, that are

  - match: set to true when the "greater or equal" condition
    evaluated to "equal". This frees the caller from the need
    to manually check whether the entry returned matches the
    search key or the new one should be inserted.

    This is the "!found" check from the above snippet.

To explain the next 2 bools, here's a small example. Consider
the tree containing two elements {token, partition key}:

   { 3, "a" }, { 5, "z" }

As the collection is sorted they go in the order shown. Next,
this is what the lower_bound would return for some cases:

   { 3, "z" } -> { 5, "z" }
   { 4, "a" } -> { 5, "z" }
   { 5, "a" } -> { 5, "z" }

Apparently, the lower bound for those 3 elements are the same,
but the code-flows of emplacing them before one differ drastically.

   { 3, "z" } : need to get previous element from the tree and
                push the element to it's vector's back
   { 4, "a" } : need to create new element in the tree and populate
                its empty vector with the single element
   { 5, "a" } : need to put the new element in the found tree
                element right before the found vector position

To make one of the above decisions the .emplace_before would need
to perform another set of comparisons of keys and elements.
Fortunately, the needed information was already known inside the
lower_bound call and can be reported via the hint.

Said that,

  - key_match: set to true if tree.lower_bound() found the element
    for the Key (which is token). For above examples this will be
    true for cases 3z and 5a.

  - key_tail: set to true if the tree element was found, but when
    comparing values from array the bounding element turned out
    to belong to the next tree element and the iterator was ++-ed.
    For above examples this would be true for case 3z only.

And the last, but not least -- the "erase self" feature. Which is
given only the cache_entry pointer at hands remove it from the
collection. To make this happen we need to make two steps:

1. get the array the entry sits in
2. get the b+ tree node the vectors sits in

Both methods are provided by array_trusted_bounds and bplus::tree.
So, when we need to get iterator from the given T pointer, the algo
looks like

- Walk back the T array untill hitting the head element
- Call array_trusted_bounds::from_element() getting the array
- Construct b+ iterator from obtained array
- Construct the double_decker iterator from b+ iterator and from
  the number of "steps back" from above
- Call double_decker::iterator.erase()

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-14 16:29:53 +03:00
Pavel Emelyanov
eb70644c1c intrusive-array: Array with trusted bounds
A plain array of elements that grows and shrinks by
constructing the new instance from an existing one and
moving the elements from it.

Behaves similarly to vector's external array, but has
0-bytes overhead. The array bounds (0-th and N-th
elemements) are determined by checking the flags on the
elements themselves. For this the type must support
getters and setters for the flags.

To remove an element from array there's also a nothrow
option that drops the requested element from array,
shifts the righter ones left and keeps the trailing
unused memory (so called "train") until reconstruction
or destruction.

Also comes with lower_bound() helper that helps keeping
the elements sotred and the from_element() one that
returns back reference to the array in which the element
sits.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-14 16:29:49 +03:00
Pavel Emelyanov
95f15ea383 utils: B+ tree implementation
// The story is at
// https://groups.google.com/forum/#!msg/scylladb-dev/sxqTHM9rSDQ/WqwF1AQDAQAJ

This is the B+ version which satisfies several specific requirements
to be suitable for row-cache usage.

1. Insert/Remove doesn't invalidate iterators
2. Elements should be LSA-compactable
3. Low overhead of data nodes (1 pointer)
4. External less-only comparator
5. As little actions on insert/delete as possible
6. Iterator walks the sorted keys

The design, briefly is:

There are 3 types of nodes: inner, leaf and data, inner and leaf
keep build-in array of N keys and N(+1) nodes. Leaf nodes sit in
a doubly linked list. Data nodes live separately from the leaf ones
and keep pointers on them. Tree handler keeps pointers on root and
left-most and right-most leaves. Nodes do _not_ keep pointers or
references on the tree (except 3 of them, see below).

changes in v9:

- explicitly marked keys/kids indices with type aliases
- marked the whole erase/clear stuff noexcept
- disposers now accept object pointer instead of reference
- clear tree in destructor
- added more comments
- style/readability review comments fixed

Prior changes

**
- Add noexcepts where possible
- Restrict Less-comparator constraint -- it must be noexcept
- Generalized node_id
- Packed code for beging()/cbegin()

**
- Unsigned indices everywhere
- Cosmetics changes

**
- Const iterators
- C++20 concepts

**
- The index_for() implmenetation is templatized the other way
  to make it possible for AVX key search specialization (further
  patching)

**
- Insertion tries to push kids to siblings before split

  Before this change insertion into full node resulted into this
  node being split into two equal parts. This behaviour for random
  keys stress gives a tree with ~2/3 of nodes half-filled.

  With this change before splitting the full node try to push one
  element to each of the siblings (if they exist and not full).
  This slows the insertion a bit (but it's still way faster than
  the std::set), but gives 15% less total number of nodes.

- Iterator method to reconstruct the data at the given position

  The helper creates a new data node, emplaces data into it and
  replaces the iterator's one with it. Needed to keep arrays of
  data in tree.

- Milli-optimize erase()
  - Return back an iterator that will likely be not re-validated
  - Do not try to update ancestors separation key for leftmost kid

  This caused the clear()-like workload work poorly as compared to
  std:set. In particular the row_cache::invalidate() method does
  exactly this and this change improves its timing.

- Perf test to measure drain speed
- Helper call to collect tree counters

**
- Fix corner case of iterator.emplace_before()
- Clean heterogenous lookup API
- Handle exceptions from nodes allocations
- Explicitly mark places where the key is copied (for future)
- Extend the tree.lower_bound() API to report back whether
  the bound hit the key or not
- Addressed style/cleanness review comments

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-14 16:29:43 +03:00
Juliusz Stasiewicz
c69075bbef cql3/restrictions: exclude NULLs from comparison in filtering
NULLs used to give false positives in GT, LT, GEQ and LEQ ops
performed upon `ALLOW FILTERING`. That was a consequence of
not distinguishing NULL from an empty buffer. This patch excludes
NULLs on high level, preventing them from entering any comparison,
i.e. it assumes that any binary operator should return `false`
whenever one of the operands is NULL (note: ATM filters such as
`...WHERE x=NULL ALLOW FILTERING` return empty sets anyway).

`restriction_test/regular_col_slice` had to be updated accordingly.

Fixes #6295
2020-07-14 12:59:01 +02:00
Pavel Emelyanov
9d38846ed2 test: Move perf measurement helpers into header
To use the code in new perf tests in next patches.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-07-14 12:58:26 +03:00
Nadav Har'El
8e3be5e7d6 alternator test: configurable temporary directory
The test/alternator/run script creates a temporary directory for the Scylla
database in /tmp. The assumption was that this is the fastest disk (usually
even a ramdisk) on the test machine, and we didn't need anything else from
it.

But it turns out that on some systems, /tmp is actually a slow disk, so
this patch adds a way to configure the temporary directory - if the TMPDIR
environment variable exists, it is used instead of /tmp. As before this
patch, a temporary subdirectry is created in $TMPDIR, and this subdirectory
is automatically deleted when the test ends.

The test.py script already passes an appropriate TMPDIR (testlog/$mode),
which after this patch the Alternator test will use instead of /tmp.

Fixes #6750

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200713193023.788634-1-nyh@scylladb.com>
2020-07-14 08:52:22 +03:00
Nadav Har'El
35f7048228 alternator: CreateTable with bad Tags shouldn't create a table
Currently, if a user tries to CreateTable with a forbidden set of tags,
e.g., the Tags list is too long or contains an invalid value for
system:write_isolation, then the CreateTable request fails but the table
is still created. Without the tag of course.

This patch fixes this bug, and adds two test cases for it that fail
before this patch, and succeed with it. One of the test cases is
scylla_only because it checks the Scylla-specific system:write_isolation
tag, but the second test case works on DynamoDB as well.

What this patch does is to split the update_tags() function into two
parts - the first part just parses the Tags, validates them, and builds
a map. Only the second part actually writes the tags to the schema.
CreateTable now does the first part early, before creating the table,
so failure in parsing or validating the Tags will not leave a created
table behind.

Fixes #6809.

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200713120611.767736-1-nyh@scylladb.com>
2020-07-13 17:14:44 +03:00
Nadav Har'El
f549d147ea alternator: fix Expected's "NULL" operator with missing AttributeValueList
The "NULL" operator in Expected (old-style conditional operations) doesn't
have any parameters, so we insisted that the AttributeValueList be empty.
However, we forgot to allow it to also be missing - a possibility which
DynamoDB allows.

This patch adds a test to reproduce this case (the test passes on DyanmoDB,
fails on Alternator before this patch, and succeeds after this patch), and
a fix.

Fixes #6816.

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200709161254.618755-1-nyh@scylladb.com>
2020-07-10 07:45:02 +02:00
Benny Halevy
3ce86a7160 test: restrictions_test: set_contains: uncomment check depnding on #6797
Now that #6797 is fixed.

Refs #5763

Cc: Dejan Mircevski <dejan@scylladb.com>
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>

Test: restrictions_test(debug)
Message-Id: <20200709123703.955897-1-bhalevy@scylladb.com>
2020-07-09 17:56:09 +03:00
Nadav Har'El
9042161ba3 merge: cdc: better pre/postimages for complicated batches
Merged pull request https://github.com/scylladb/scylla/pull/6741
by Piotr Dulikowski:

This PR changes the algorithm used to generate preimages and postimages
in CDC log. While its behavior is the same for non-batch operations
(with one exception described later), it generates pre/postimages that
are organized more nicely, and account for multiple updates to the same
row in one CQL batch.

Fixes #6597, #6598

Tests:
- unit(dev), for each consecutive commit
- unit(debug), for the last commit

Previous method

The previous method worked on a per delta row basis. First, the base
table is queried for the current state of the rows being modified in
the processed mutation (this is called the "preimage query"). Then,
for each delta row (representing a modification of a row):

    If preimage is enabled and the row was already present in the table,
    a corresponding preimage row is inserted before the delta row.
    The preimage row contains data taken directly from the preimage
    query result. Only columns that are modified by the delta are
    included in the preimage.
    If postimage is enabled, then a postimage row is inserted after the
    delta row. The postimage row contains data which was a result of
    taking row data directly from the preimage query result and applying
    the change the corresponding delta row represented. All columns
    of the row are included in the postimage.

The above works well for simple cases such like singular CQL INSERT,
UPDATE, DELETE, or simple CQL BATCH-es. An example:

cqlsh:ks> BEGIN UNLOGGED BATCH
			INSERT INTO tbl (pk, ck, v) VALUES (0, 1, 111);
			INSERT INTO tbl (pk, ck, v) VALUES (0, 2, 222);
			APPLY BATCH;
cqlsh:ks> SELECT "cdc$batch_seq_no", "cdc$operation", "cdc$ttl",
			pk, ck, v from ks.tbl_scylla_cdc_log ;

 cdc$batch_seq_no | cdc$operation | cdc$ttl | pk | ck | v
------------------+---------------+---------+----+----+-----
...snip...
                0 |             0 |    null |  0 |  1 | 100
                1 |             2 |    null |  0 |  1 | 111
                2 |             9 |    null |  0 |  1 | 111
                3 |             0 |    null |  0 |  2 | 200
                4 |             2 |    null |  0 |  2 | 222
                5 |             9 |    null |  0 |  2 | 222

Preimage rows are represented by cdc operation 0, and postimage by 9.
Please note that all rows presented above share the same value of
cdc$time column, which was not shown here for brevity.

Problems with previous approach

This simple algorithm has some conceptual and implementational problems
which arise when processing more complicated CQL BATCH-es. Consider
the following example:

cqlsh:ks> BEGIN UNLOGGED BATCH
			INSERT INTO tbl (pk, ck, v1) VALUES (0, 0, 1) USING TTL 1000;
			INSERT INTO tbl (pk, ck, v2) VALUES (0, 0, 2) USING TTL 2000;
			APPLY BATCH;
cqlsh:ks> SELECT "cdc$batch_seq_no", "cdc$operation", "cdc$ttl",
			pk, ck, v1, v2 FROM tbl_scylla_cdc_log;

 cdc$batch_seq_no | cdc$operation | cdc$ttl | pk | ck | v1   | v2
------------------+---------------+---------+----+----+------+------
...snip...
                0 |             0 |    null |  0 |  0 | null |    0
                1 |             2 |    2000 |  0 |  0 | null |    2
                2 |             9 |    null |  0 |  0 |    0 |    2
                3 |             0 |    null |  0 |  0 |    0 | null
                4 |             1 |    1000 |  0 |  0 |    1 | null
                5 |             9 |    null |  0 |  0 |    1 |    0

A single cdc group (corresponding to rows sharing the same cdc$time)
might have more than one delta that modify the same row. For example,
this happens when modifying two columns of the same row with
different TTLs - due to our choice of CDC log schema, we must
represent such change with two delta rows.

It does not make sense to present a postimage after the first delta
and preimage before the second - both deltas are applied
simultaneously by the same CQL BATCH, so the middle "image" is purely
imaginary and does not appear at any point in the table.

Moreover, in this example, the last postimage is wrong - v1 is updated,
but v2 is not. None of the postimages presented above represent the
final state of the row.

New algorithm

The new algorithm works now on per cdc group basis, not delta row.
When starting processing a CQL BATCH:

    Load preimage query results into a data structure representing
    current state of the affected rows.

For each cdc group:

    For each row modified within the group, a preimage is produced,
    regardless if the row was present in the table. The preimage
    is calculated based on the current state. Only include columns
    that are modified for this row within the group.
    For each delta, produce a delta row and update the current state
    accordingly.
    Produce postimages in the same way as preimages - but include all
    columns for each row in the postimage.

The new algorithm produces postimage correctly when multiple deltas
affect one, because the state of the row is updated on the fly.

This algorithm moves preimage and postimage rows to the beginning and
the end of the cdc group, accordingly. This solves the problem of
imaginary preimages and postimages appearing inside a cdc group.

Unfortunately, it is possible for one CQL BATCH to contain changes that
use multiple timestamps. This will result in one CQL BATCH creating
multiple cdc groups, with different cdc$time. As it is impossible, with
our choice of schema, to tell that those cdc groups were created from
one CQL BATCH, instead we pretend as if those groups were separate CQL
operations. By tracking the state of the affected rows, we make sure
that preimage in later groups will reflect changes introduces in
previous groups.

One more thing - this algorithm should have the same results for
singular CQL operations and simple CQL BATCH-es, with one exception.
Previously, preimage not produced if a row was not present in the
table. Now, the preimage row will appear unconditionally - it will have
nulls in place of column values.

* 'cdc-pre-postimage-persistence' of github.com:piodul/scylla:
  cdc: fix indentation
  cdc: don't update partition state when not needed
  cdc: implement pre/postimage persistence
  cdc: add interface for producing pre/postimages
  cdc: load preimage query result into partition state fields
  cdc: introduce fields for keeping partition state
  cdc: rename set_pk_columns -> allocate_new_log_row
  cdc: track batch_no inside transformer
  cdc: move cdc$time generation to transformer
  cdc: move find_timestamp to split.cc
  cdc: introduce change_processor interface
  cdc: remove redundant schema arguments from cdc functions
  cdc: move management of generated mutations inside transformer
  cdc: move preimage result set into a field of transformer
  cdc: keep ts and tuuid inside transformer
  cdc: track touched parts of mutations inside transformer
  cdc: always include preimage for affected rows
2020-07-09 16:55:55 +03:00
Piotr Sarna
75dbaa0834 test: add alternator test for incorrect numeric values
The test case is put inside test_manual_requests suite, because
boto3 validates numeric inputs and does not allow passing arbitrary
incorrect values.

Tests: unit(dev), alternator(local, remote)

Message-Id: <ac2baedc2ea61f0d857e7c01839f34cd15f7e02d.1594289250.git.sarna@scylladb.com>
2020-07-09 13:58:33 +03:00
Dejan Mircevski
d956233a80 cql_query_test: Drop get() on cquery_nofail result
cquery_nofail returns the query result, not a future.  Invoking .get()
on its result is unnecessary.  This just happened to compile because
shared_ptr has a get() method with the same signature as future::get.

Tests: cql_query_test unit test (dev)

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
2020-07-09 13:52:52 +03:00
Nadav Har'El
9ff9cd37c3 alternator test: tests for the number type
We had some tests for the number type in Alternator and how it can be
stored, retrieved, calculated and sorted, but only had rudementary tests
for the allowed magnitude and precision of numbers.

This patch creates a new test file, test_number.py, with tests aiming to
check exactly the supported magnitudes and precision of numbers.

These tests verify two things:

1. That Alternator's number type supports the full precision and magnitude
   that DynamoDB's number type supports. We don't want to see precision
   or magnitude lost when storing and retrieving numbers, or when doing
   calculations on them.

2. That Alternator's number type does not have *better* precision or
   magnitude than DynamoDB does. If it did, users may be tempted to rely
   on that implementation detail.

The three tests of the first type pass; But all four tests of the second
type xfail: Alternator currently stores numbers using big_decimal which
has unlimited precision and almost-unlimited magnitude, and is not yet
limited by the precision and magnitude allowed by DynamoDB.
This is a known issue - Refs #6794 - and these four new xfailing tests
will can be used to reproduce that issue.

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200707204824.504877-1-nyh@scylladb.com>
2020-07-09 07:38:36 +02:00
Piotr Dulikowski
246f8da6f6 cdc: implement pre/postimage persistence
Moves responsibility for generating pre/postimage rows from the
"process_change" method to "produce_preimage" and "produce_postimage".
This commit actually affects the contents of generated CDC log
mutations.

Added a unit test that verifies more complicated cases with CQL BATCH.
2020-07-08 15:36:41 +02:00
Piotr Dulikowski
f907cab156 cdc: remove redundant schema arguments from cdc functions
A `mutation` object already has a reference to its schema. It does not
make sense to call functions changed in this commit with a different
schema.
2020-07-08 15:36:40 +02:00
Piotr Dulikowski
027d20c654 cdc: always include preimage for affected rows
This changes the current algorithm so that the preimage row will not be
skipped if the corresponding rows was not present in preimage query
results.
2020-07-08 15:36:40 +02:00
Rafael Ávila de Espíndola
b10beead61 memtable_snapshot_source: Avoid a std::bad_alloc crash
_should_compact is a condition_variable and condition_variable::wait()
allocates memory.

Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Message-Id: <20200706223201.903072-1-espindola@scylladb.com>
2020-07-08 15:21:50 +02:00
Avi Kivity
7ea9ee27dd Merge 'aggregates: Use type-specific comparators in min/max' from Juliusz
"
For collections and UDTs the `MIN()` and `MAX()` functions are
generated on the fly. Until now they worked by comparing just the
byte representations of their arguments.

This patch employs specific per-type comparators to provide semantically
sensible, dynamically created aggregates.

Fixes #6768
"

* jul-stas-6768-use-type-comparators-for-minmax:
  tests: Test min/max on set
  aggregate_fcts: Use per-type comparators for dynamic types
2020-07-08 15:07:57 +03:00
Juliusz Stasiewicz
f08e0e10be tests: Test min/max on set
Expected behavior is the lexicographical comparison of sets
(element by element), so this test was failing when raw byte
representations were compared.
2020-07-08 13:39:15 +02:00
Avi Kivity
b0698dfb38 Merge 'Rewrite CQL3 restriction representation' from dekimir
"
This is the first stage of replacing the existing restrictions code with a new representation. It adds a new class `expression` to replace the existing class `restriction`. Lots of the old code is deleted, though not all -- that will come in subsequent stages.

Tests: unit (dev, debug restrictions_test), dtest (next-gating)
"

* dekimir-restrictions-rewrite:
  cql3/restrictions: Drop dead code
  cql3/restrictions: Use free functions instead of methods
  cql3/restrictions: Create expression objects
  cql3/restrictions: Add free functions over new classes
  cql3/restrictions: Add new representation
2020-07-08 10:22:17 +03:00
Dejan Mircevski
37ebe521e3 cql3/restrictions: Use free functions instead of methods
Instead of `restriction` class methods, use the new free functions.
Specific replacement actions are listed below.

Note that class `restrictions` (plural) remains intact -- both its
methods and its type hierarchy remain intact for now.

Ensure full test coverage of the replacement code with new file
test/boost/restrictions_test.cc and some extra testcases in
test/cql/*.

Drop some existing tests because they codify buggy behaviour
(reference #6369, #6382).  Drop others because they forbid relation
combinations that are now allowed (eg, mixing equality and
inequality, comparing to NULL, etc.).

Here are some specific categories of what was replaced:

- restriction::is_foo predicates are replaced by using the free
  function find_if; sometimes it is used transitively (see, eg,
  has_slice)

- restriction::is_multi_column is replaced by dynamic casts (recall
  that the `restrictions` class hierarchy still exists)

- utility methods is_satisfied_by, is_supported_by, to_string, and
  uses_function are replaced by eponymous free functions; note that
  restrictions::uses_function still exists

- restriction::apply_to is replaced by free function
  replace_column_def

- when checking infinite_bound_range_deletions, the has_bound is
  replaced by local free function bounded_ck

- restriction::bounds and restriction::value are replaced by the more
  general free function possible_lhs_values

- using free functions allows us to simplify the
  multi_column_restriction and token_restriction hierarchies; their
  methods merge_with and uses_function became identical in all
  subclasses, so they were moved to the base class

- single_column_primary_key_restrictions<clustering_key>::needs_filtering
  was changed to reuse num_prefix_columns_that_need_not_be_filtered,
  which uses free functions

Fixes #5799.
Fixes #6369.
Fixes #6371.
Fixes #6372.
Fixes #6382.

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
2020-07-07 23:08:09 +02:00
Nadav Har'El
0143aaa5a8 merge: Forbid internal schema changes for distributed tables
Merged patch set from Piotr Sarna:

This series addresses issue #6700 again (it was reopened),
by forbidding all non-local schema changes to be performed
from within the database via CQL interface. These changes
are dangerous since they are not directly propagated to other
nodes.

Tests: unit(dev)
Fixes #6700

Piotr Sarna (4):
  test: make schema changes in query_processor_test global
  cql3: refuse to change schema internally for distributed tables
  test: expand testing internal schema changes
  cql3: add explanatory comments to execute_internal

 cql3/query_processor.hh                      | 13 ++++++++++++-
 cql3/statements/alter_table_statement.cc     |  6 ------
 cql3/statements/schema_altering_statement.cc | 15 +++++++++++++++
 test/boost/cql_query_test.cc                 |  8 ++++++--
 test/boost/query_processor_test.cc           | 16 ++++++++--------
 5 files changed, 41 insertions(+), 17 deletions(-)
2020-07-07 18:27:16 +03:00
Piotr Sarna
8ecae38d6b test: expand testing internal schema changes
... in order to ensure that not only ALTER TABLE, but also other
schema altering statements are not allowed for distributed
tables/keyspaces.
2020-07-07 10:02:58 +02:00
Piotr Sarna
9bdf17a804 test: make schema changes in query_processor_test global
Now that schema changes are going to be forbidden for non-local tables,
query_processor_test is updated accordingly.
2020-07-07 09:09:40 +02:00
Botond Dénes
5ebe2c28d1 db/view: view_update_generator: re-balance wait/signal on the register semaphore
The view update generator has a semaphore to limit concurrency. This
semaphore is waited on in `register_staging_sstable()` and later the
unit is returned after the sstable is processed in the loop inside
`start()`.
This was broken by 4e64002, which changed the loop inside `start()` to
process sstables in per table batches, however didn't change the
`signal()` call to return the amount of units according to the number of
sstables processed. This can cause the semaphore units to dry up, as the
loop can process multiple sstables per table but return just a single
unit. This can also block callers of `register_staging_sstable()`
indefinitely as some waiters will never be released as under the right
circumstances the units on the semaphore can permanently go below 0.
In addition to this, 4e64002 introduced another bug: table entries from
the `_sstables_with_tables` are never removed, so they are processed
every turn. If the sstable list is empty, there won't be any update
generated but due to the unconditional `signal()` described above, this
can cause the units on the semaphore to grow to infinity, allowing
future staging sstables producers to register a huge amount of sstables,
causing memory problems due to the amount of sstable readers that have
to be opened (#6603, #6707).
Both outcomes are equally bad. This patch fixes both issues and modifies
the `test_view_update_generator` unit test to reproduce them and hence
to verify that this doesn't happen in the future.

Fixes: #6774
Refs: #6707
Refs: #6603

Tests: unit(dev)
Signed-off-by: Botond Dénes <bdenes@scylladb.com>
Message-Id: <20200706135108.116134-1-bdenes@scylladb.com>
2020-07-07 08:53:00 +02:00
Dejan Mircevski
921dbd0978 cql/restrictions: Handle WHERE a>0 AND a<0
WHERE clauses with start point above the end point were handled
incorrectly.  When the slice bounds are transformed to interval
bounds, the resulting interval is interpreted as wrap-around (because
start > end), so it contains all values above 0 and all values below
0.  This is clearly incorrect, as the user's intent was to filter out
all possible values of a.

Fix it by explicitly short-circuiting to false when start > end.  Add
a test case.

Fixes #5799.

Tests: unit (dev)

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
2020-07-06 19:11:20 +03:00
Piotr Sarna
446b89f408 test: move json tests from manual/ to boost/
Manual tests are, as the name suggests, not run automatically,
which makes them more prone to regressions. JSON tests are
fast and correct, so there's no reason for them to be marked
as manual.

Message-Id: <dea75b0a0d1c238d12382a28840978884ac6ec2c.1594023481.git.sarna@scylladb.com>
2020-07-06 11:24:12 +03:00
Piotr Sarna
83ab41c76d test: add json test for parsing from map
Our JSON legacy helper functions for parsing documents to/from
string maps are indirectly tested by several unit tests, e.g.
caching_options_test.cc. They however lacked one corner case
detected only by dtest - parsing an empty map from a null JSON document.
This case is hereby added in order to prevent future regressions.

Message-Id: <df8243bd083b2ba198df665aeb944c8710834736.1594020411.git.sarna@scylladb.com>
2020-07-06 10:28:55 +03:00
Avi Kivity
cc891a5de8 Merge "Convert a few uses of sstring to std::string_view" from Rafael
"
This series converts an API to use std::string_view and then converts
a few sstring variables to be constexpr std::string_view. This has the
advantage that a constexpr variables cannot be part of any
initialization order problem.
"

* 'espindola/convert-to-constexpr' of https://github.com/espindola/scylla:
  auth: Convert sstring variables in common.hh to constexpr std::string_view
  auth: Convert sstring variables in default_authorizer to constexpr std::string_view
  cql_test_env: Make ks_name a constexpr std::string_view
  class_registry: Use std::string_view in (un)?qualified_name
2020-07-05 17:08:54 +03:00
Rafael Ávila de Espíndola
33af0c293f cql_test_env: Make ks_name a constexpr std::string_view
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
2020-07-03 12:28:20 -07:00
Nadav Har'El
8e3ecc30a9 merge: Migrate from libjsoncpp to rjson
Merged patch series by Piotr Sarna:

The alternator project was in need of a more optimized
JSON library, which resulted in creating "rjson" helper functions.
Scylla generally used libjsoncpp for its JSON handling, but in  order
to reduce the dependency hell, the usage is now migrated
to rjson, which is faster and offers the same functionality.

The original plan was to be able to drop the dependency
on libjsoncpp-lib altogether and remove it from install-dependencies.sh,
but one last usage of it remains in our test suite,
namely cql_repl. The tool compares its output JSON textually,
so it depends on how a library presents JSON - what are the delimeters,
indentation, etc. It's possible to provide a layer of translation
to force rjson to print in an identical format, but the other issue
is that libjsoncpp keeps subobjects sorted by their name,
while rjson uses an unordered structure.
There are two possible solutions for the last remaining usage
of libjsoncpp:
 1. change our test suite to compare JSON documents with a JSON parser,
    so that we don't rely on internal library details
 2. provide a layer of translation which forces rjson to print
    its objects in a format idential to libjsoncpp.
(1.) would be preferred, since now we're also vulnerable for changes
inside libjsoncpp itself - if they change anything in their output
format, tests would start failing. The issue is not critical however,
so it's left for later.

Tests: unit(dev), manual(json_test),
       dtest(partitioner_tests.TestPartitioner.murmur3_partitioner_test)

Piotr Sarna (8):
  alternator,utils: move rjson.hh to utils/
  alternator: remove ambiguous string overloads in rjson
  rjson: add parse_to_map helper function
  rjson: add from_string_map function
  rjson: add non-throwing parsing
  rjson: move quote_json_string to rjson
  treewide: replace libjsoncpp usage with rjson
  configure: drop json.cc and json.hh helpers

 alternator/base64.hh                |   2 +-
 alternator/conditions.cc            |   2 +-
 alternator/executor.hh              |   2 +-
 alternator/expressions.hh           |   2 +-
 alternator/expressions_types.hh     |   2 +-
 alternator/rmw_operation.hh         |   2 +-
 alternator/serialization.cc         |   2 +-
 alternator/serialization.hh         |   2 +-
 alternator/server.cc                |   2 +-
 caching_options.hh                  |   9 +-
 cdc/log.cc                          |   4 +-
 column_computation.hh               |   5 +-
 configure.py                        |   3 +-
 cql3/functions/functions.cc         |   4 +-
 cql3/statements/update_statement.cc |  24 ++--
 cql3/type_json.cc                   | 212 ++++++++++++++++++----------
 cql3/type_json.hh                   |   7 +-
 db/legacy_schema_migrator.cc        |  12 +-
 db/schema_tables.cc                 |   1 -
 flat_mutation_reader.cc             |   1 +
 index/secondary_index.cc            |  80 +++++------
 json.cc                             |  80 -----------
 json.hh                             | 113 ---------------
 schema.cc                           |  25 ++--
 test/boost/cql_query_test.cc        |   9 +-
 test/manual/json_test.cc            |   4 +-
 test/tools/cql_repl.cc              |   1 +
 {alternator => utils}/rjson.cc      |  75 +++++++++-
 {alternator => utils}/rjson.hh      |  40 +++++-
 29 files changed, 344 insertions(+), 383 deletions(-)
 delete mode 100644 json.cc
 delete mode 100644 json.hh
 rename {alternator => utils}/rjson.cc (86%)
 rename {alternator => utils}/rjson.hh (81%)
2020-07-03 18:23:56 +02:00
Piotr Sarna
4cb79f04b0 treewide: replace libjsoncpp usage with rjson
In order to eventually switch to a single JSON library,
most of the libjsoncpp usage is dropped in favor of rjson.
Unfortunately, one usage still remains:
test/utils/test_repl utility heavily depends on the *exact textual*
format of its output JSON files, so replacing a library results
in all tests failing because of differences in formatting.
It is possible to force rjson to print its documents in the exact
matching format, but that's left for later, since the issue is not
critical. It would be nice though if our test suite compared
JSON documents with a real JSON parser, since there are more
differences - e.g. libjsoncpp keeps children of the object
sorted, while rapidjson uses an unordered data structure.
This change should cause no change in semantics, it strives
just to replace all usage of libjsoncpp with rjson.
2020-07-03 10:27:23 +02:00
Piotr Sarna
1b37517aab rjson: move quote_json_string to rjson
This utility function is used for type serialization,
but it also has a dedicated unit test, so it needs to be globally
reachable.
2020-07-03 10:27:23 +02:00