If we are redefining the log table, we need to ensure any dropped
columns are registered in "dropped_columns" table, otherwise clients will not
be able to read data older than now.
Includes unit test.
Should probably be backported to all CDC enabled versions.
Fixes#10473Closes#10474
CDC registers to the table-creation hook (before_create_column_family)
to add a second table - the CDC log table - to the same keyspace.
The handler function (on_before_update_column_family() in cdc/log.cc)
wants to retrieve the keyspace's definition, but that does NOT WORK if
we create the keyspace and table in one operation (which is exactly what
we intend to do in Alternator to solve issue #9868) - because at the
time of the hook, the keyspace does not yet exist in the schema.
It turns out that on_before_update_column_family() does not REALLY need
the keyspace. It needed it to pass it on to make_create_table_mutations()
but that function doesn't use the keyspace parameter passed to it! All
it needs is the keyspace's name - which is in the schema anyway and
doesn't need to be looked up.
So in this patch we fix make_create_table_mutations() to not require the
unused keyspace parameter - and fix the CDC code not to look for the
keyspace that is no longer needed.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220215162342.622509-1-nyh@scylladb.com>
Base tables that use compact storage may have a special artificial
column that has an empty type.
c010cefc4d fixed the main CDC path to
handle such columns correctly and to not include them in the CDC Log
schema.
This patch makes sure that generation of preimage ignores such empty
column as well.
Fixes#9876Closes#9910
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
Move replica-oriented classes to the replica namespace. The main
classes moved are ::database, ::keyspace, and ::table, but a few
ancillary classes are also moved. There are certainly classes that
should be moved but aren't (like distributed_loader) but we have
to start somewhere.
References are adjusted treewide. In many cases, it is obvious that
a call site should not access the replica (but the data_dictionary
instead), but that is left for separate work.
scylla-gdb.py is adjusted to look for both the new and old names.
The database, keyspace, and table classes represent the replica-only
part of the objects after which they are named. Reading from a table
doesn't give you the full data, just the replica's view, and it is not
consistent since reconciliation is applied on the coordinator.
As a first step in acknowledging this, move the related files to
a replica/ subdirectory.
The problem was that such a command:
```
alter table ks.cf with cdc={'ttl': 120};
```
would assume that "enabled" parameter is the default ("false") and,
in effect, disable CDC on that table. This commit forces the user
to specify that key.
Fixes#6475Closes#9720
This PR finally removes the `term` class and replaces it with `expression`.
* There was some trouble with `lwt_cache_id` in `expr::function_call`.
The current code works the following way:
* for each `function_call` inside a `term` that describes a pk restriction, `prepare_context::add_pk_function_call` is called.
* `add_pk_function_call` takes a `::shared_ptr<cql3::functions::function_call>`, sets its `cache_id` and pushes this shared pointer onto a vector of all collected function calls
* Later when some condiition is met we want to clear cache ids of all those collected function calls. To do this we iterate through shared pointers collected in `prepare_context` and clear cache id for each of them.
This doesn't work with `expr::function_call` because it isn't kept inside a shared pointer.
To solve this I put the `lwt_cache_id` inside a shared pointer and then `prepare_context` collects these shared pointers to cache ids.
I also experimented with doing this without any shared pointers, maybe we could just walk through the expression and clear the cache ids ourselves. But the problem is that expressions are copied all the time, we could clear the cache in one place, but forget about a copy. Doing it using shared pointers more closely matches the original behaviour.
The experiment is on the [term2-pr3-backup-altcache](https://github.com/cvybhu/scylla/tree/term2-pr3-backup-altcache) branch
* `shared_ptr<term>` being `nullptr` could mean:
* It represents a cql value `null`
* That there is no value, like `std::nullopt` (for example in `attributes.hh`)
* That it's a mistake, it shouldn't be possible
A good way to distinguish between optional and mistake is to look for `my_term->bind_and_get()`, we then know that it's not an optional value.
* On the other hand `raw_value` cased to bool means:
* `false` - null or unset
* `true` - some value, maybe empty
I ran a simple benchmark on my laptop to see how performance is affected:
```
build/release/test/perf/perf_simple_query --smp 1 -m 1G --operations-per-shard 1000000 --task-quota-ms 10
```
* On master (a21b1fbb2f) I get:
```
176506.60 tps ( 77.0 allocs/op, 12.0 tasks/op, 45831 insns/op)
median 176506.60 tps ( 77.0 allocs/op, 12.0 tasks/op, 45831 insns/op)
median absolute deviation: 0.00
maximum: 176506.60
minimum: 176506.60
```
* On this branch I get:
```
172225.30 tps ( 75.1 allocs/op, 12.1 tasks/op, 46106 insns/op)
median 172225.30 tps ( 75.1 allocs/op, 12.1 tasks/op, 46106 insns/op)
median absolute deviation: 0.00
maximum: 172225.30
minimum: 172225.30
```
Closes#9481
* github.com:scylladb/scylla:
cql3: Remove remaining mentions of term
cql3: Remove term
cql3: Rename prepare_term to prepare_expression
cql3: Make prepare_term return an expression instead of term
cql3: expr: Add size check to evaluate_set
cql3: expr: Add expr::contains_bind_marker
cql3: expr: Rename find_atom to find_binop
cql3: expr: Add find_in_expression
cql3: Remove term in operations
cql3: Remove term in relations
cql3: Remove term in multi_column_restrictions
cql3: Remove term in term_slice, rename to bounds_slice
cql3: expr: Remove term in expression
cql3: expr: Add evaluate_IN_list(expression, options)
cql3: Remove term in column_condition
cql3: Remove term in select_statement
cql3: Remove term in update_statement
cql3: Use internal cql format in insert_prepared_json_statement cache
types: Add map_type_impl::serialize(range of <bytes, bytes>)
cql3: Remove term in cql3/attributes
cql3: expr: Add constant::view() method
cql3: expr: Implement fill_prepare_context(expression)
cql3: expr: add expr::visit that takes a mutable expression
cql3: expr: Add receiver to expr::bind_variable
This is an undocumented feature that causes confusion so let's get rid
of it.
tests: unit(dev)
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Closes#9639
This is to push the service towards general idea that each
component should have its own config and db::config to stay
in main.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
All callers has been patched already. This argument can now
be used to replace get_local_storage_proxy().get_db().local()
call.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Get rid of unused includes of seastar/util/{defer,closeable}.hh
and add a few that are missing from source files.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Fixes#9103
compare overload was declared as "bool" even though it is a tri-cmp.
causes us to never use the speed-up shortcut (lessen search set),
in turn meaning more overhead for collections.
Closes#9104
When a table with compact storage has no regular column (only primary
key columns), an artificial column of type empty is added. Such column
type can't be returned via CQL so CDC Log shouldn't contain a column
that reflects this artificial column.
This patch does two things:
1. Make sure that CDC Log schema does not contain columns that reflect
the artificial column from a base table.
2. When composing mutation to CDC Log, ommit the artificial column.
Fixes#8410
Test: unit(dev)
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Closes#8988
"
Storage service needs migration notifier reference to pass it to cdc
service via get_local_storage_service(). This set removes
- get_local_storage_service from cdc
- migration notifier from storage service
- db_context::builder from cdc (released nuclear binding energy)
tests: unit(dev)
"
* 'br-cdc-no-storage-service' of https://github.com/xemul/scylla:
storage_service: Remove migration notifier dependency
cdc: Remove db_context::builder
cdc: Provide migration notifier right at once
cdc: Remove db_context::builder::with_migration_notifier
Right now the builder is just an opaque transfer between cdc_service
constructor args and cdc_service's db_context constructor args.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The only way db_context's migration notifier reference is set up
is via cdc_service->db_context::builder->.build chain of calls.
Since the builder's notifier optional reference is always
disengaged (the .with_migration_notifier is removed by previous
patch) the only possible notifier reference there is from the
storage service which, in turn, is the same as in main.cc.
Said that -- push the notifier reference onto db_context directly.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Before this change, cdc$deleted_ columns were all NULL in pre-images.
Lack of such information made it hard to correctly interpret the
pre-image rows, for example:
INSERT INTO tbl(pk, ck, v, v2) VALUES (1, 1, null, 1);
INSERT INTO tbl(pk, ck, v2) VALUES (1, 1, 1);
For this example, pre-image generated for the second operation
would look like this (in both 'true' and 'full' pre-image mode):
pk=1, ck=1, v=NULL, cdc$deleted_v=NULL, v2=1
v=NULL has two meanings:
1. If pre-image was in 'true' mode, v=NULL describes that v was not
affected (affected columns: pk, ck, v2).
2. If pre-image was in 'full' mode, v=NULL describes that v was equal
to NULL in the pre-image.
Therefore, to properly decode pre-images you would need to know in
which mode pre-image was configured on the CDC-enabled table at the
moment this CDC log row was inserted. There is no way to determine
such information (you can only check a current mode of pre-image).
A solution to this problem is to fill in the cdc$deleted_ columns
for pre-images. After this change, for the INSERT described above, CDC
now generates the following log row:
If in pre-image 'true' mode:
pk=1, ck=1, v=NULL, cdc$deleted_v=NULL, v2=1
If in pre-image 'full' mode:
pk=1, ck=1, v=NULL, cdc$deleted_v=true, v2=1
A client library now can properly decode a pre-image row. If it sees
a NULL value, it can now check the cdc$deleted_ column to determine
if this NULL value was a part of pre-image or it was omitted due to
not being an affected column in the delta operation.
No such change is necessary for the post-image rows, as those images
are always generated in the 'full' mode.
Additional example of trouble decoding pre-images before this change.
tbl2 - 'true' pre-image mode, tbl3 - 'full' pre-image mode:
INSERT INTO tbl2(pk, ck, v, v2) VALUES (1, 1, 5, 1);
INSERT INTO tbl3(pk, ck, v, v2) VALUES (1, 1, null, 1);
INSERT INTO tbl2(pk, ck, v2) VALUES (1, 1, 1);
generated pre-image:
pk=1, ck=1, v=NULL, cdc$deleted_v=NULL, v2=1
INSERT INTO tbl3(pk, ck, v2) VALUES (1, 1, 1);
generated pre-image:
pk=1, ck=1, v=NULL, cdc$deleted_v=NULL, v2=1
Both pre-images look the same, but:
1. v=NULL in tbl2 describes v being omitted from the pre-image.
2. v=NULL in tbl3 described v being NULL in the pre-image.
storage_proxy.hh is huge and includes many headers itself, so
remove its inclusions from headers and re-add smaller headers
where needed (and storage_proxy.hh itself in source files that
need it).
Ref #1.
Improve the exception message of providing invalid "ttl" value to the
table.
Previously, if you executed a CREATE TABLE query with invalid "ttl"
value, you would get a non-descriptive error message:
CREATE TABLE ks.t(pk int, PRIMARY KEY(pk)) WITH cdc = {'enabled': true, 'ttl': 'invalid'};
ServerError: stoi
This commit adds more descriptive exception messages:
CREATE TABLE ks.t(pk int, PRIMARY KEY(pk)) WITH cdc = {'enabled': true, 'ttl': 'kgjhfkjd'};
ConfigurationException: Invalid value for CDC option "ttl": kgjhfkjd
CREATE TABLE ks.t(pk int, PRIMARY KEY(pk)) WITH cdc = {'enabled': true, 'ttl': '75747885787487'};
ConfigurationException: Invalid CDC option: ttl too large
Add validation of "enable" and "postimage" CDC options. Both options
are boolean options, but previously they were not validated, meaning
you could issue a query:
CREATE TABLE ks.t(pk int, PRIMARY KEY(pk)) WITH cdc = {'enabled': 'dsfdsd'};
and it would be executed without any errors, silently interpreting
"dsfdsd" as false.
This commit narrows possible values of those boolean CDC options to
false, true, 0, 1. After applying this change, issuing the query above
would result in this error message:
ConfigurationException: Invalid value for CDC option "enabled": dsfdsd
CDC log uses `bytes` to deal with cells and their values, and linearizes all
values indiscriminately. This series makes a switch from `bytes` to
`managed_bytes` to avoid that linearization.
Fixes#7506.
Closes#8429
* github.com:scylladb/scylla:
cdc: log: change yet another occurence of `bytes` to `managed_bytes`
cdc: log: switch the remaining usages of `bytes` to `managed_bytes` in collection_visitor
cdc: log: change `deleted_elements` in log_mutation_builder from bytes to managed_bytes
cdc: log: rewrite collection merge to use managed_bytes instead of bytes
cdc: log: don't linearize collections in get_preimage_col_value
cdc: log: change return type of get_preimage_col_value to managed_bytes
cdc: log: remove an unnecessary copy in process_row_visitor::live_atomic_cell
cdc: log: switch cell_map from bytes to managed_bytes
cdc: log: change the argument of log_mutation_builder::set_value to managed_bytes_view
cdc: log: don't linearize the primary key in log_mutation_builder
atomic_cell: add yet another variant of make_live for managed_bytes_view
compound: add explode_fragmented
A follow up for the patch for #7611. This change was requested
during review and moved out of #7611 to reduce its scope.
The patch switches UUID_gen API from using plain integers to
hold time units to units from std::chrono.
For one, we plan to switch the entire code base to std::chrono units,
to ensure type safety. Secondly, using std::chrono units allows to
increase code reuse with template metaprogramming and remove a few
of UUID_gen functions that beceme redundant as a result.
* switch get_time_UUID(), unix_timestamp(), get_time_UUID_raw(), switch
min_time_UUID(), max_time_UUID(), create_time_safe() to
std::chrono
* remove unused variant of from_unix_timestamp()
* remove unused get_time_UUID_bytes(), create_time_unsafe(),
redundant get_adjusted_timestamp()
* inline get_raw_UUID_bytes()
* collapse to similar implementations of get_time_UUID()
* switch internal constants to std::chrono
* remove unnecessary unique_ptr from UUID_gen::_instance
Message-Id: <20210406130152.3237914-2-kostja@scylladb.com>
In preparation for removing linearization from abstract_type::compare,
add options to avoid linearization in tuple_deserializing_iterator.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Refs #7961Fixes#8014
Instead of doing a deep copy of input, we keep assume ownership and build
rows of the views therein, potentially retaining fragmented data as-is
avoiding premature linearization.
Note that this is not all sugar and flowers though. Any data access will
by nature be more expensive, and the view collections we create are
potentially just as expensive as copying for small cells.
Otoh, it allows writing code using this that avoids data copying,
depending on destination.
v2:
* Fixed wrong collection reserved in visitor
* Changed row index from shared ptr to ref
* Moved typedef
* Removed non-existing constructors
* Added const ref to index build
* Fixed raft usage after rebase
v3:
* Changed shared_ptr to unique
Currently all management of CDC generations happens in storage_service,
which is a big ball of mud that does many unrelated things.
Previous commits have introduced a new service for managing CDC
generations. This code moves most of the relevant code to this new
service.
However, some part still remains in storage_service: the bootstrap
procedure, which happens inside storage_service, must also do some
initialization regarding CDC generations, for example: on restart it
must retrieve the latest known generation timestamp from disk; on
bootstrap it must create a new generation and announce it to other
nodes. The order of these operations w.r.t the rest of the startup
procedure is important, hence the startup procedure is the only right
place for them.
Still, what remains in storage_service is a small part of the entire
CDC generation management logic; most of it has been moved to the
new service. This includes listening for generation changes and
updating the data structures for performing CDC log writes (cdc::metadata).
Furthermore these functions now return futures (and are internally
coroutines), where previously they required a seastar::async context.
Due to small value optimization used in `bytes`, views to `bytes` stored
in `vector` can be invalidated when the vector resizes, resulting in
use-after-free and data corruption. Fix that.
Fixes#8117
Commit aab6b0ee27 introduced the
controversial new IMR format, which relied on a very template-heavy
infrastructure to generate serialization and deserialization code via
template meta-programming. The promise was that this new format, beyond
solving the problems the previous open-coded representation had (working
on linearized buffers), will speed up migrating other components to this
IMR format, as the IMR infrastructure reduces code bloat, makes the code
more readable via declarative type descriptions as well as safer.
However, the results were almost the opposite. The template
meta-programming used by the IMR infrastructure proved very hard to
understand. Developers don't want to read or modify it. Maintainers
don't want to see it being used anywhere else. In short, nobody wants to
touch it.
This commit does a conceptual revert of
aab6b0ee27. A verbatim revert is not
possible because related code evolved a lot since the merge. Also, going
back to the previous code would mean we regress as we'd revert the move
to fragmented buffers. So this revert is only conceptual, it changes the
underlying infrastructure back to the previous open-coded one, but keeps
the fragmented buffers, as well as the interface of the related
components (to the extent possible).
Fixes: #5578
1. It's unused since cbe510d1b8
2. It's unsafe to keep a reference to token_metadata&
potentially across yield points.
The higher-level motivation is to make
storage_service::get_token_metadata() private so we
can control better how it's used.
For cdc, if the token_metadata is going to be needed
to the future, it'd be better get it from
db_context::_proxy.get_token_metadata_ptr().
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20201213162351.52224-2-bhalevy@scylladb.com>
