This patchset adds missing "const" function qualifiers throughout
the Scylla code base, which would make code less error-prone.
The changeset incorporates Kostja's work regarding const qualifiers
in the cql code hierarchy along with a follow-up patch addressing the
review comment of the corresponding patch set (the patch subject is
"cql: propagate const property through prepared statement tree.").
By default, semaphore exceptions bring along very little context:
either that a semaphore was broken or that it timed out.
In order to make debugging easier without introducing significant
runtime costs, a notion of named semaphore is added.
A named semaphore is simply a semaphore with statically defined
name, which is present in its errors, bringing valuable context.
A semaphore defined as:
auto sem = semaphore(0);
will present the following message when it breaks:
"Semaphore broken"
However, a named semaphore:
auto named_sem = named_semaphore(0, named_semaphore_exception_factory{"io_concurrency_sem"});
will present a message with at least some debugging context:
"Semaphore broken: io_concurrency_sem"
It's not much, but it would really help in pinpointing bugs
without having to inspect core dumps.
At the same time, it does not incur any costs for normal
semaphore operations (except for its creation), but instead
only uses more CPU in case an error is actually thrown,
which is considered rare and not to be on the hot path.
Refs #4999
Tests: unit(dev), manual: hardcoding a failure in view building code
invoke_on() guarantees that captures object won't be destroyed until the
future returned by the invoked function is resolved so there's no need
to move key, token, proposal for calling paxos_state::*_impl helpers.
When starting scylla daemon as non-root the initialization fails
because standard /var/lib/scylla is not accessible by regular users.
Making the default dir accessible for user is not very convenient
either, as it will cause conflicts if two or more instances of scylla
are in use.
This problem can be resolved by specifying --commitlog-directory,
--data-file-directories, etc on start, but it's too much typing. I
propose to revive Nadav's --home option that allows to move all the
directories under the same prefix in one go.
Unlike Nadav's approach the --workdir option doesn't do any tricky
manipulations with existing directories. Insead, as Pekka suggested,
the individual directories are placed under the workir if and only
if the respective option is NOT provided. Otherwise the directory
configuration is taken as is regardless of whether its absolute or
relative path.
The values substutution is done early on start. Avi suggested that
this is unsafe wrt HUP config re-read and proper paths must be
resolved on the fly, but this patch doesn't address that yet, here's
why.
First of all, the respective options are MustRestart now and the
substitution is done before HUP handler is installed.
Next, commitlog and data_file values are copied on start, so marking
the options as LiveUpdate won't make any effect.
Finally, the existing named_value::operator() returns a reference,
so returning a calculated (and thus temporary) value is not possible
(from my current understanding, correct me if I'm wrong). Thus if we
want the *_directory() to return calculated value all callers of them
must be patched to call something different (e.g. *_directory.get() ?)
which will lead to more confusion and errors.
Changes v3:
- the option is --workdir back again
- the existing *directory are only affected if unset
- default config doesn't have any of these set
- added the short -W alias
Changes v2:
- the option is --home now
- all other paths are changed to be relative
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20191119130059.18066-1-xemul@scylladb.com>
I found these mismatched types while converting some member functions
to standalone functions, since they have to use the public API that
has more type checks.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Message-Id: <20191120181213.111758-4-espindola@scylladb.com>
In this document, the detailed design and implementation of Redis API in
Scylla is provided.
v2: build: work around ragel 7 generated code bug (suggested by Avi)
Ragel 7 incorrectly emits some unused variables that don't compile.
As a workaround, sed them away.
Signed-off-by: Peng Jian <pengjian.uestc@gmail.com>
Signed-off-by: Amos Kong <amos@scylladb.com>
Those are typically symptoms of use-after-free or memory corruption in
the program. It's better to catch such error sooner than later.
That situation is also dangerous since if a valid descriptor would
land under the invalid access, not the one which was intended for the
operation, then the operation may be performed on the wrong file and
result in corruption.
Message-Id: <1565206788-31254-1-git-send-email-tgrabiec@scylladb.com>
"
This patch series adds only UDF support, UDA will be in the next patch series.
With this all CQL types are mapped to Lua. Right now we setup a new
lua state and copy the values for each argument and return. This will
be optimized once profiled.
We require --experimental to enable UDF in case there is some change
to the table format.
"
* 'espindola/udf-only-v4' of https://github.com/espindola/scylla: (65 commits)
Lua: Document the conversions between Lua and CQL
Lua: Implement decimal subtraction
Lua: Implement decimal addition
Lua: Implement support for returning decimal
Lua: Implement decimal to string conversion
Lua: Implement decimal to floating point conversion
Lua: Implement support for decimal arguments
Lua: Implement support for returning varint
Lua: Implement support for returning duration
Lua: Implement support for duration arguments
Lua: Implement support for returning inet
Lua: Implement support for inet arguments
Lua: Implement support for returning time
Lua: Implement support for time arguments
Lua: Implement support for returning timeuuid
Lua: Implement support for returning uuid
Lua: Implement support for uuid and timeuuid arguments
Lua: Implement support for returning date
Lua: Implement support for date arguments
Lua: Implement support for returning timestamp
...
There are ... signs of massive start/stop code rework in the
main() function. While fixing the sub-modules interdependencies
during start/stop I've polished these signs too, so here's the
simplest ones.
Serialize provided partition_key in such a way that the serialized value
will hash to the same token as the original key. This way when system.paxos
table is updated the update is shard local.
Message-Id: <20191114135449.GU10922@scylladb.com>
This patch resurrects Cassandra's code validating a consistency level
for CAS requests. Basically, it makes CAS requests use a special
function instead of validate_for_write to make error messages more
coherent.
Note, we don't need to resurrect requireNetworkTopologyStrategy as
EACH_QUORUM should work just fine for both CAS and non-CAS writes.
Looks like it is just an artefact of a rebase in the Cassandra
repository.
This add a wrapper around the lua interpreter so that function
executions are interruptible and return futures.
With this patch it is possible to write and use simple UDFs that take
and return integer values.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
With this it is possible to create user defined functions and
aggregates and they are saved to disk and the schema change is
propagated.
It is just not possible to call them yet.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Since seastar::streams are based on future/promise, variadic streams
suffer the same fate as variadic futures - deprecation and eventual
removal.
This patch therefore replaces a variadic stream in commitlog::read_log_file()
with a non-variadic stream, via a helper struct.
Tests: unit (dev)
Support single-statement conditional updates and as well as batches.
This patch almost fully rewrites column_condition.cc, implementing
is_satisfied_by().
Most of the remaining complications in column_condition implementation
come from the need to properly handle frozen and multi-cell
collection in predicates - up until now it was not possible
to compare entire collection values between each other. This is further
complicated since multi-cell lists and sets are returned as maps.
We can no longer assume that the columns fetched by prefetch operation
are non-frozen collections. IF EXISTS/IF NOT EXISTS condition
fetches all columns, besides, a column may be needed to check other
condition.
When fetching the old row for LWT or to apply updates on list/columns,
we now calculate precisely the list of columns to fetch.
The primary key columns are also included in CAS batch result set,
and are thus also prefetched (the user needs them to figure out which
statements failed to apply).
The patch is cross-checked for compatibility with cassandra-3.11.4-1545-g86812fa502
but does deviate from the origin in handling of conditions on static
row cells. This is addressed in future series.
Paxos protocol relies on replicas having a state that persists over
crashes/restarts. This patch defines such state and stores it in the
database itself in the paxos table to make it persistent.
The stored state is:
in_progress_ballot - promised ballot
proposal - accepted value
proposal_ballot - the ballot of the accepted value
most_recent_commit - most recently learned value
most_recent_commit_at - the ballot of the most recently learned value
Add a cluster feature for non-frozen UDTs.
If the cluster supports non-frozen UDTs, do not return an error
message when trying to create a table with a non-frozen user type.
is_value_compatible_with_internal and update_user_type were generalized
to the non-frozen case.
For now, all user_type_impls in the code are non-multi-cell (frozen).
This will be changed in future commits.
`collection_type_impl::serialize_mutation_form`
became `collection_mutation(_view)_description::serialize`.
Previously callers had to cast their data_type down to collection_type
to use serialize_mutation_form. Now it's done inside `serialize`.
In the future `serialize` will be generalized to handle UDTs.
`collection_type_impl::deserialize_mutation_form`
became a free standing function `deserialize_collection_mutation`
with similiar benefits. Actually, noone needs to call this function
manually because of the next paragraph.
A common pattern consisting of linearizing data inside a `collection_mutation_view`
followed by calling `deserialize_mutation_form` has been abstracted out
as a `with_deserialized` method inside collection_mutation_view.
serialize_mutation_form_only_live was removed,
because it hadn't been used anywhere.
collection_type_impl::mutation became collection_mutation_description.
collection_type_impl::mutation_view became collection_mutation_view_description.
These classes now reside inside collection_mutation.hh.
Additional documentation has been written for these classes.
Related function implementations were moved to collection_mutation.cc.
This makes it easier to generalize these classes to non-frozen UDTs in future commits.
The new names (together with documentation) better describe their purpose.
Scylla 3.1.0 broke the serialization format for TTLs. Later versions
corrected it, but if a cluster was originally installed as 3.1.0,
it will use the broken serialization forever. This configuration option
allows upgrades from 3.1.0 to succeed, by enabling the broken format
even for later versions.
Merged patch series from Piotr Sarna:
Calculating the select statement for given view_info structure
used to work fine, but once local indexes were introduced, a subtle
bug appeared: the legacy token column does not exist in local indexes
and a valid clustering key column was omitted instead.
That results in potentially incorrect partition slices being used later
in read-before-write.
There's a long term plan for removing select_statement from
view info altogether, but nonetheless the bug needs to be fixed first.
Branch: master, 3.1
Tests: unit(dev) + manual confirmation that a correct legacy column is picked
Calculating the select statement for given view_info structure
used to work fine, but once local indexes were introduced, a subtle
bug appeared: the legacy token column does not exist in local indexes
and a valid clustering key column was omitted instead.
That results in potentially incorrect partition slices being used later
in read-before-write.
There's a long term plan for removing select_statement from
view info altogether, but nonetheless the bug needs to be fixed first.
The config entry will be used to turn authorization for alternator
requests on and off. The default is currently off, since the key store
is not implemented yet.
Merged patch series from Piotr Sarna:
This series adds HTTPS support for Alternator.
The series comes with --https option added to alternator-test, which makes
the test harness run all the tests with HTTPS instead of HTTP. All the tests
pass, albeit with security warnings that a self-signed x509 certificate was
used and it should not be trusted.
Fixes#5042
Refs scylladb/seastar#685
Patches:
docs: update alternator entry on HTTPS
alternator-test: suppress the "Unverified HTTPS request" warning
alternator-test: add HTTPS info to README.md
alternator-test: add HTTPS to test_describe_endpoints
alternator-test: add --https parameter
alternator: add HTTPS support
config: add alternator HTTPS port
"
Fix races that may lead to use-after-free events and file system level exceptions
during shutdown and drain.
The root cause of use-after-free events in question is that space_watchdog blocks on
end_point_hints_manager::file_update_mutex() and we need to make sure this mutex is alive as long as
it's accessed even if the corresponding end_point_hints_manager instance
is destroyed in the context of manager::drain_for().
File system exceptions may occur when space_watchdog attempts to scan a
directory while it's being deleted from the drain_for() context.
In case of such an exception new hints generation is going to be blocked
- including for materialized views, till the next space_watchdog round (in 1s).
Issues that are fixed are #4685 and #4836.
Tested as follows:
1) Patched the code in order to trigger the race with (a lot) higher
probability and running slightly modified hinted handoff replace
dtest with a debug binary for 100 times. Side effect of this
testing was discovering of #4836.
2) Using the same patch as above tested that there are no crashes and
nodes survive stop/start sequences (they were not without this series)
in the context of all hinted handoff dtests. Ran the whole set of
tests with dev binary for 10 times.
"
* 'hinted_handoff_race_between_drain_for_and_space_watchdog_no_global_lock-v2' of https://github.com/vladzcloudius/scylla:
hinted handoff: fix a race on a directory removal between space_watchdog and drain_for()
hinted handoff: make taking file_update_mutex safe
db::hints::manager::drain_for(): fix alignment
db::hints::manager: serialize calls to drain_for()
db::hints: cosmetics: identation and missing method qualifier
"
This is a collection of assorted patches that will be needed for LWT.
Most of them are trivial, but one touches a lot of files, so have a
good chance to cause rebase headache (I already had to rebase it on
top of Alternator). Lets push them earlier instead of carrying them in
the lwt branch.
"
* 'gleb/lwt-prepare-v2' of github.com:scylladb/seastar-dev:
lwt: make _last_timestamp_micros static
lwt: Add client_state::get_timestamp_for_paxos() function
lwt: Pass client_state reference all the way to storage_proxy::query
exceptions: Add a constructor for unavailable_exception that allows providing a custom message
serializer: Add std::variant support
lwt: Add missing functions to utils/UUID_gen.hh
When the toppartitions operation gathers results, it copies partition
keys with their schema_ptr:s. When these schema_ptr:s are copies
or destroyed, they can cause leaks or premature frees of the schema
in its original shard since reference count operations in are not atomic.
Fix that by converting the schema_ptr to a global_schema_ptr during
transportation.
Fixes#5104 (direct bug)
Fixes#5018 (schema prematurely freed, toppartitions previously executed on that node)
Fixes#4973 (corrupted memory pool of the same size class as schema, toppartitions previously executed on that node)
Tests: new test added that fails with the existing code in debug mode,
manual toppartitions test
Copying schema_ptrs across shards results in memory corruption since
lw_shared_ptr does not use atomic operations for reference counts.
Prevent that by converting schema_ptr:s to global_schema_ptr:s before
shipping them across shards in the map operation, and converting them
back to local schema_ptr:s in the reduce operation.
This allows keys from different stages in the schema's like to compare equal.
This is safe since the partition key cannot change, unlike the rest of the schema.
More importantly, it will allow us to compare keys made local after a pass through
global_schema_ptr, which does not guarantee that the schema_ptr conversion will be
the same even when starting with the same global_schema_ptr.
client_state holds a state to generate monotonically increasing unique
timestamp. Queries with a SERIAL consistency level need it to generate
a paxos round.
In the system.types table a user type refers to another by name. When
a user type is modified, only its entry in the table is changed.
At runtime a user type has direct pointer to the types it uses. To
handle the discrepancy we need to recreate any dependent types when a
entry in system.types changes.
Fixes#5049
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
