The test is currently flaky, writes can fail with "Too many in flight
hints: 10485936". See scylladb/scylladb#23565 for more details.
We suspect that scylladb/scylladb#23565 is caused by an infrastructure
issue - slow disks on some machines we run CI jobs on.
Since the test fails often and investigation doesn't seem to be easy,
we first deflake the test in this patch by disabling hinted handoff.
For replacing nodes, we provide `cfg` because there should have been
`cfg` in the first place. The test was correct anyway because:
- `tablets_mode_for_new_keyspaces` is set to `true` by default in
test/cluster/suite.yaml,
- `endpoint_snitch` is set to `GossipingPropertyFileSnitch` by default
if the property file is provided in `ScyllaServer.__init__`.
Ref scylladb/scylladb#23565
We should backport this patch to 2025.2 because this test is also flaky
on CI jobs using 2025.2. Older branches don't have this test.
Closes scylladb/scylladb#24364
(cherry picked from commit 8756c233e0)
Fixes#24756Closesscylladb/scylladb#24757
`dirty_memory_manager` tracks two quantities about memtable memory usage:
"real" and "unspooled" memory usage.
"real" is the total memory usage (sum of `occupancy().total_space()`)
by all memtable LSA regions, plus a upper-bound estimate of the size of
memtable data which has already moved to the cache region but isn't
evictable (merged into the cache) yet.
"unspooled" is the difference between total memory usage by all memtable
LSA regions, and the total flushed memory (sum of `_flushed_memory`)
of memtables.
`dirty_memory_manager` controls the shares of compaction and/or blocks
writes when these quantities cross various thresholds.
"Total flushed memory" isn't a well defined notion,
since the actual consumption of memory by the same data can vary over
time due to LSA compactions, and even the data present in memtable can
change over the course of the flush due to removals of outdated MVCC versions.
So `_flushed_memory` is merely an approximation computed by `flush_reader`
based on the data passing through it.
This approximation is supposed to be a conservative lower bound.
In particular, `_flushed_memory` should be not greater than
`occupancy().total_space()`. Otherwise, for example, "unspooled" memory
could become negative (and/or wrap around) and weird things could happen.
There is an assertion in `~flush_memory_accounter` which checks that
`_flushed_memory < occupancy().total_space()` at the end of flush.
But it can fail. Without additional treatment, the memtable reader sometimes emits
data which is already deleted. (In particular, it emites rows covered by
a partition tombstone in a newer MVCC version.)
This data is seen by `flush_reader` and accounted in `_flushed_memory`.
But this data can be garbage-collected by the `mutation_cleaner` later during the
flush and decrease `total_memory` below `_flushed_memory`.
There is a piece of code in `mutation_cleaner` intended to prevent that.
If `total_memory` decreases during a `mutation_cleaner` run,
`_flushed_memory` is lowered by the same amount, just to preserve the
asserted property. (This could also make `_flushed_memory` quite inaccurate,
but that's considered acceptable).
But that only works if `total_memory` is decreased during that run. It doesn't
work if the `total_memory` decrease (enabled by the new allocator holes made
by `mutation_cleaner`'s garbage collection work) happens asynchronously
(due to memory reclaim for whatever reason) after the run.
This patch fixes that by tracking the decreases of `total_memory` closer to the
source. Instead of relying on `mutation_cleaner` to notify the memtable if it
lowers `total_memory`, the memtable itself listens for notifications about
LSA segment deallocations. It keeps `_flushed_memory` equal to the reader's
estimate of flushed memory decreased by the change in `total_memory` since the
beginning of flush (if it was positive), and it keeps the amount of "spooled"
memory reported to the `dirty_memory_manager` at `max(0, _flushed_memory)`.
Fixes scylladb/scylladb#21413
Backport candidate because it fixes a crash that can happen in existing stable branches.
- (cherry picked from commit 7d551f99be)
- (cherry picked from commit 975e7e405a)
Parent PR: #21638Closesscylladb/scylladb#24604
* github.com:scylladb/scylladb:
memtable: ensure _flushed_memory doesn't grow above total memory usage
replica/memtable: move region_listener handlers from dirty_memory_manager to memtable
optimized_clang.sh trains the compiler using profile-guided optimization
(pgo). However, while doing that, it builds scylladb using its own profile
stored in pgo/profiles and decompressed into build/profile.profdata. Due
to the funky directory structure used for training the compiler, that
path is invalid during the training and the build fails.
The workaround was to build on a cloud machine instead of a workstation -
this worked because the cloud machine didn't have git-lfs installed, and
therefore did not see the stored profile, and the whole mess was averted.
To make this work on a machine that does have access to stored profiles,
disable use of the stored profile even if it exists.
Fixes#22713Closesscylladb/scylladb#24571
(cherry picked from commit 52f11e140f)
Closesscylladb/scylladb#24621
test_dict_memory_limit trains new dictionaries and checks (via metrics)
that the old dictionaries are appropriately cleaned up.
The problem is that the cleanup is asynchronous (because the lifetimes
are handled by foreign_ptr, which sends the destructor call
to the owner shard asynchronously), so the metrics might be
checked a few milliseconds before the old dictionary is cleaned up.
The dict lifetimes are lazy on purpose, the right thing to do is
to just let the test retry the check.
Fixesscylladb/scylladb#24516Closesscylladb/scylladb#24526
(cherry picked from commit cace55aaaf)
Closesscylladb/scylladb#24653
In ed3e4f33fd we introduced new connection throttling feature which is controlled by uninitialized_connections_semaphore_cpu_concurrency config. But live updating of it was broken, this patch fixes it.
When the temporary value from observer() is destroyed, it disconnects from updateable_value, so observation stops right away. We need to retain the observer.
Backport: to 2025.2 where this feature was added
Fixes: https://github.com/scylladb/scylladb/issues/24557
- (cherry picked from commit c6a25b9140)
- (cherry picked from commit 45392ac29e)
- (cherry picked from commit 68ead01397)
Parent PR: #24484Closesscylladb/scylladb#24679
* github.com:scylladb/scylladb:
test: add test for live updates of generic server config
utils: don't allow do discard updateable_value observer
generic_server: fix connections semaphore config observer
The exponent of a big decimal string is parsed as an int32, adjusted for
the removed fractional part, and stored as an int32. When parsing values
like `1.23E-2147483647`, the unscaled value becomes `123`, and the scale
is adjusted to `2147483647 + 2 = 2147483649`. This exceeds the int32
limit, and since the scale is stored as an int32, it overflows and wraps
around, losing the value.
This patch fixes that the by parsing the exponent as an int64 value and
then adjusting it for the fractional part. The adjusted scale is then
checked to see if it is still within int32 limits before storing. An
exception is thrown if it is not within the int32 limits.
Note that strings with exponents that exceed the int32 range, like
`0.01E2147483650`, were previously not parseable as a big decimal. They
are now accepted if the final adjusted scale fits within int32 limits.
For the above value, unscaled_value = 1 and scale = -2147483648, so it
is now accepted. This is in line with how Java's `BigDecimal` parses
strings.
Fixes: #24581
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Closesscylladb/scylladb#24640
(cherry picked from commit 279253ffd0)
Closesscylladb/scylladb#24692
Currently the test indiscriminately injects failures into the flushes of
any table, via the IO extension mechanism. The tests want to check that
the node correctly handles the IO error by self isolating, however the
indiscriminate IO errors can have unintended consequences when they hit
raft, leading to disorderly shutdown and failure of the tests. Testing
raft's resiliency to IO errors if of course worth doing, but it is not
the goal of this particular test, so to avoid the fallout, the IO errors
are limited to the test tables only.
Fixes: https://github.com/scylladb/scylladb/issues/24637Closesscylladb/scylladb#24638
(cherry picked from commit ee6d7c6ad9)
Closesscylladb/scylladb#24743
Although valid for compact tables, non-full (or empty) clustering key prefixes are not handled for row keys when writing sstables. Only the present components are written, consequently if the key is empty, it is omitted entirely.
When parsing sstables, the parsing code unconditionally parses a full prefix.
This mis-match results in parsing failures, as the parser parses part of the row content as a key resulting in a garbage key and subsequent mis-parsing of the row content and maybe even subsequent partitions.
Introduce a new system table: `system.corrupt_data` and infrastructure similar to `large_data_handler`: `corrupt_data_handler` which abstracts how corrupt data is handled. The sstable writer now passes rows such corrupt keys to the corrupt data handler. This way, we avoid corrupting the sstables beyond parsing and the rows are also kept around in system.corrupt_data for later inspection and possible recovery.
Add a full-stack test which checks that rows with bad keys are correctly handled.
Fixes: https://github.com/scylladb/scylladb/issues/24489
The bug is present in all versions, has to be backported to all supported versions.
- (cherry picked from commit 92b5fe8983)
- (cherry picked from commit 0753643606)
- (cherry picked from commit b0d5462440)
- (cherry picked from commit 093d4f8d69)
- (cherry picked from commit 678deece88)
- (cherry picked from commit 64f8500367)
- (cherry picked from commit b931145a26)
- (cherry picked from commit 3e1c50e9a7)
- (cherry picked from commit 46ff7f9c12)
- (cherry picked from commit ebd9420687)
- (cherry picked from commit aae212a87c)
- (cherry picked from commit 592ca789e2)
- (cherry picked from commit edc2906892)
Parent PR: #24492Closesscylladb/scylladb#24744
* github.com:scylladb/scylladb:
test/boost/sstable_datafile_test: add test for corrupt data
sstables/mx/writer: handler rows with empty keys
test/lib/cql_assertions: introduce columns_assertions
sstables: add corrupt_data_handler to sstables::sstables
tools/scylla-sstable: make large_data_handler a local
db: introduce corrupt_data_handler
mutation: introduce frozen_mutation_fragment_v2
mutation/mutation_partition_view: read_{clustering,static}_row(): return row type
mutation/mutation_partition_view: extract de-ser of {clustering,static} row
idl-compiler.py: generate skip() definition for enums serializers
idl: extract full_position.idl from position_in_partition.idl
db/system_keyspace: add apply_mutation()
db/system_keyspace: introduce the corrupt_data table
After paxos state is repaired in begin_and_repair_paxos we need to
re-check the state regardless if write back succeeded or not. This
is how the code worked originally but it was unintentionally changed
when co-routinized in 61b2e41a23.
Fixes#24630Closesscylladb/scylladb#24651
(cherry picked from commit 5f953eb092)
Closesscylladb/scylladb#24703
In the present scenario, the bootstrapping node undergoes synchronize phase after
initialization of group0, then enters post_raft phase and becomes fully ready for
group0 operations. The topology coordinator is agnostic of this and issues stream
ranges command as soon as the node successfully completes `join_group0`. Although for
a node booting into an already upgraded cluster, the time duration for which, node
remains in synchronize phase is negligible but this race condition causes trouble in a
small percentage of cases, since the stream ranges operation fails and node fails to bootstrap.
This commit addresses this issue and updates the error throw logic to account for this
edge case and lets the node wait (with timeouts) for synchronize phase to get over instead of throwing
error.
A regression test is also added to confirm the working of this code change. The test adds a
wait in synchronize phase for newly joining node and releases only after the program counter
reaches the synchronize case in the `start_operation` function. Hence it indicates that in the
updated code, the start_operation will wait for the node to get done with the
synchronize phase instead of throwing error.
This PR fixes a bug. Hence we need to backport it.
Fixes: scylladb/scylladb#23536Closesscylladb/scylladb#23829
(cherry picked from commit 5ff693eff6)
Closesscylladb/scylladb#24628
* create a table with random schema
* generate data: random mutations + one row with bad key
* write data to sstable
* check that only good data is written to sstable
* check that the bad data was saved to system.corrupt_data
(cherry picked from commit edc2906892)
Although valid for compact tables, non-full (or empty) clustering key
prefixes are not handled for row keys when writing sstables. Only the
present components are written, consequently if the key is empty, it is
omitted entirely.
When parsing sstables, the parsing code unconditionally parses a full
prefix. This mis-match results in parsing failures, as the parser parses
part of the row content as a key resulting in a garbage key and
subsequent mis-parsing of the row content and maybe even subsequent
partitions.
Use the recently introduced corrupt_data_handler to handle rows with
such corrupt keys. This way, we avoid corrupting the sstables beyond
parsing and the rows are also kept around in system.corrupt_data for
later inspection and possible recovery.
(cherry picked from commit 592ca789e2)
Similar to how large_data_handler is handled, propagate through
sstables::sstables_manager and store its owner: replica::database.
Tests and tools are also patched. Mostly mechanical changes, updating
constructors and patching callers.
(cherry picked from commit ebd9420687)
Similar to large_data_handler, this interface allows sstable writers to
delegate the handling of corrupt data.
Two implementations are provided:
* system_table_corrupt_data_handler - saved corrupt data in
system.corrupt_data, with a TTL=10days (non-configurable for now)
* nop_corrupt_data_handler - drops corrupt data
(cherry picked from commit 3e1c50e9a7)
Mirrors frozen_mutation_fragment and shares most of the underlying
serialization code, the only exception is replacing range_tombstone with
range_tombstone_change in the mutation fragment variant.
(cherry picked from commit b931145a26)
Instead of mutation_fragment, let caller convert into mutation_fragment.
Allows reuse in future callers which will want to convert to
mutation_fragment_v2.
(cherry picked from commit 64f8500367)
From the visitor in frozen_mutation_fragment::unfreeze(). We will want
to re-use it in the future frozen_mutation_fragment_v2::unfreeze().
Code-movement only, the code is not changed.
(cherry picked from commit 678deece88)
Currently they only have the declaration and so far they got away with
it, looks like no users exists, but this is about to change so generate
the definition too.
(cherry picked from commit 093d4f8d69)
A future user of position_in_partition.idl doesn't need full_position
and so doesn't want to include full_position.hh to fix compile errors
when including position_in_partition.idl.hh.
Extract it to a separate idl file: it has a single user in a
storage_proxy VERB.
(cherry picked from commit b0d5462440)
Allow applying writes in the form of mutations directly to the keyspace.
Allows lower-level mutation API to build writes. Advantageous if writes
can contain large cells that would otherwise possibly cause large
allocation warnings if used via the internal CQL API.
(cherry picked from commit 0753643606)
To serve as a place to store corrupt mutation fragments. These fragments
cannot be written to sstables, as they would be spread around by
compaction and/or repair. They even might make parsing the sstable
impossible. So they are stored in this special table instead, kept
around to be inspected later and possibly restored if possible.
(cherry picked from commit 92b5fe8983)
test_repair_task_progress checks the progress of children of root
repair task. However, nothing ensures that the children are
already created.
Wait until at least one child of a root repair task is created.
Fixes: #24556.
Closesscylladb/scylladb#24560
(cherry picked from commit 0deb9209a0)
Closesscylladb/scylladb#24655
We replace the documentation of the old recovery procedure with the
documentation of the new recovery procedure.
The new recovery procedure requires the Raft-based topology to be
enabled, so to remove the old procedure from the documentation,
we must assume users have the Raft-based topology enabled.
We can do it in 2025.2 because the upgrade guides to 2025.1 state that
enabling the Raft-based topology is a mandatory step of the upgrade.
Another reminder is the upgrade guides to 2025.2.
Since we rely on the Raft-based topology being enabled, we remove the
obsolete parts of the documentation.
We will make the Raft-based topology mandatory in the code in the
future, hopefully in 2025.3. For this reason, we also don't touch the
dev docs in this PR.
Fixes scylladb/scylladb#24530
Requires backport to 2025.2 because 2025.2 contains the new recovery
procedure.
- (cherry picked from commit 4e256182a0)
- (cherry picked from commit 203ea5d8f9)
Parent PR: #24583Closesscylladb/scylladb#24702
* https://github.com/scylladb/scylladb:
docs: rely on the Raft-based topology being enabled
docs: handling-node-failures: document the new recovery procedure
In 2025.2, we don't force enabling the Raft-based topology in the code,
but we stated in the upgrade guides that it's a mandatory step of the
upgrade to 2025.1. We also remind users to enable the Raft-based
topology in the upgrade guides to 2025.2. Hence, we can rely in the
the documentation on the Raft-based topology being enabled. If it is
still disabled, we can just send the user to the upgrade guides. Hence:
- we remove all documentation related to enabling the Raft-based
topology, enabling the Raft-based schema (enabled Raft-based topology
implies enabled Raft-based schema), and the gossip-based topology,
- we can replace the documentation of the old manual recovery procedure
with the documentation of the new manual recovery procedure (done in
the previous commit).
(cherry picked from commit 203ea5d8f9)
We replace the documentation of the old recovery procedure with the
documentation of the new recovery procedure.
We can get rid of the old procedure from the documentation because
we requested users to enable the Raft-based topology during upgrades to
2025.1 and 2025.2.
We leave the note that enabling the Raft-based topology is required to
use the new recovery procedure just in case, since we didn't force
enabling the Raft-based topology in the code.
(cherry picked from commit 4e256182a0)
If the object returned from observe() is destructured,
it stops observing, potentially causing subtle bugs.
Typically, the observer object is retained as a class member.
(cherry picked from commit 45392ac29e)
When temporary value returned by observer() is destructed it
disconnects from updateable_value so the code immediately stops
observing.
To fix it we need to retain the observer in the class object.
(cherry picked from commit c6a25b9140)
dirty_memory_manager tracks two quantities about memtable memory usage:
"real" and "unspooled" memory usage.
"real" is the total memory usage (sum of `occupancy().total_space()`)
by all memtable LSA regions, plus a upper-bound estimate of the size of
memtable data which has already moved to the cache region but isn't
evictable (merged into the cache) yet.
"unspooled" is the difference between total memory usage by all memtable
LSA regions, and the total flushed memory (sum of `_flushed_memory`)
of memtables.
dirty_memory_manager controls the shares of compaction and/or blocks
writes when these quantities cross various thresholds.
"Total flushed memory" isn't a well defined notion,
since the actual consumption of memory by the same data can vary over
time due to LSA compactions, and even the data present in memtable can
change over the course of the flush due to removals of outdated MVCC versions.
So `_flushed_memory` is merely an approximation computed by `flush_reader`
based on the data passing through it.
This approximation is supposed to be a conservative lower bound.
In particular, `_flushed_memory` should be not greater than
`occupancy().total_space()`. Otherwise, for example, "unspooled" memory
could become negative (and/or wrap around) and weird things could happen.
There is an assertion in ~flush_memory_accounter which checks that
`_flushed_memory < occupancy().total_space()` at the end of flush.
But it can fail. Without additional treatment, the memtable reader sometimes emits
data which is already deleted. (In particular, it emites rows covered by
a partition tombstone in a newer MVCC version.)
This data is seen `flush_reader` and accounted in `_flushed_memory`.
But this data can be garbage-collected by the mutation_cleaner later during the
flush and decrease `total_memory` below `_flushed_memory`.
There is a piece of code in mutation_cleaner intended to prevent that.
If `total_memory` decreases during a `mutation_cleaner` run,
`_flushed_memory` is lowered by the same amount, just to preserve the
asserted property. (This could also make `_flushed_memory` quite inaccurate,
but that's considered acceptable).
But that only works if `total_memory` is decreased during that run. It doesn't
work if the `total_memory` decrease (enabled by the new allocator holes made
by `mutation_cleaner`'s garbage collection work) happens asynchronously
(due to memory reclaim for whatever reason) after the run.
This patch fixes that by tracking the decreases of `total_memory` closer to the
source. Instead of relying on `mutation_cleaner` to notify the memtable if it
lowers `total_memory`, the memtable itself listens for notifications about
LSA segment deallocations. It keeps `_flushed_memory` equal to the reader's
estimate of flushed memory decreased by the change in `total_memory` since the
beginning of flush (if it was positive), and it keeps the amount of "spooled"
memory reported to the `dirty_memory_manager` at `max(0, _flushed_memory)`.
(cherry picked from commit 975e7e405a)
The memtable wants to listen for changes in its `total_memory` in order
to decrease its `_flushed_memory` in case some of the freed memory has already
been accounted as flushed. (This can happen because the flush reader sees
and accounts even outdated MVCC versions, which can be deleted and freed
during the flush).
Today, the memtable doesn't listen to those changes directly. Instead,
some calls which can affect `total_memory` (in particular, the mutation cleaner)
manually check the value of `total_memory` before and after they run, and they
pass the difference to the memtable.
But that's not good enough, because `total_memory` can also change outside
of those manually-checked calls -- for example, during LSA compaction, which
can occur anytime. This makes memtable's accounting inaccurate and can lead
to unexpected states.
But we already have an interface for listening to `total_memory` changes
actively, and `dirty_memory_manager`, which also needs to know it,
does just that. So what happens e.g. when `mutation_cleaner` runs
is that `mutation_cleaner` checks the value of `total_memory` before it runs,
then it runs, causing several changes to `total_memory` which are picked up
by `dirty_memory_manager`, then `mutation_cleaner` checks the end value of
`total_memory` and passes the difference to `memtable`, which corrects
whatever was observed by `dirty_memory_manager`.
To allow memtable to modify its `_flushed_memory` correctly, we need
to make `memtable` itself a `region_listener`. Also, instead of
the situation where `dirty_memory_manager` receives `total_memory`
change notifications from `logalloc` directly, and `memtable` fixes
the manager's state later, we want to only the memtable listen
for the notifications, and pass them already modified accordingl
to the manager, so there is no intermediate wrong states.
This patch moves the `region_listener` callbacks from the
`dirty_memory_manager` to the `memtable`. It's not intended to be
a functional change, just a source code refactoring.
The next patch will be a functional change enabled by this.
(cherry picked from commit 7d551f99be)
Register the current space_source_fn in an RAII
object that resets monitor._space_source to the
previous function when the RAII object is destroyed.
Use space_source_registration in database_test::
mutation_dump_generated_schema_deterministic_id_version
to prevent use-after-stack-return in the test.
Fixes#24314
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closesscylladb/scylladb#24342
(cherry picked from commit 8b387109fc)
Closesscylladb/scylladb#24392
Truncate doesn't really go well with concurrent writes. The fix (#23560) exposed
a preexisting fragility which I missed.
1) truncate gets RP mark X, truncated_at = second T
2) new sstable written during snapshot or later, also at second T (difference of MS)
3) discard_sstables() get RP Y > saved RP X, since creation time of sstable
with RP Y is equal to truncated_at = second T.
So the problem is that truncate is using a clock of second granularity for
filtering out sstables written later, and after we got low mark and truncate time,
it can happen that a sstable is flushed later within the same second, but at a
different millisecond.
By switching to a millisecond clock (db_clock), we allow sstables written later
within the same second from being filtered out. It's not perfect but
extremely unlikely a new write lands and get flushed in the same
millisecond we recorded truncated_at timepoint. In practice, truncate
will not be used concurrently to writes, so this should be enough for
our tests performing such concurrent actions.
We're moving away from gc_clock which is our cheap lowres_clock, but
time is only retrieved when creating sstable objects, which frequency of
creation is low enough for not having significant consequences, and also
db_clock should be cheap enough since it's usually syscall-less.
Fixes#23771.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closesscylladb/scylladb#24426
(cherry picked from commit 2d716f3ffe)
Closesscylladb/scylladb#24435
By default, cluster tests have skip_wait_for_gossip_to_settle=0 and
ring_delay_ms=0. In tests with gossip topology, it may lead to a race,
where nodes see different state of each other.
In case of test_auth_v2_migration, there are three nodes. If the first
node already knows that the third node is NORMAL, and the second node
does not, the system_auth tables can return incomplete results.
To avoid such a race, this commit adds a check that all nodes see other
nodes as NORMAL before any writes are done.
Refs: #24163Closesscylladb/scylladb#24185
(cherry picked from commit 555d897a15)
Closesscylladb/scylladb#24520
The contract in mutation_reader.hh says:
```
// pr needs to be valid until the reader is destroyed or fast_forward_to()
// is called again.
future<> fast_forward_to(const dht::partition_range& pr) {
```
`test_fast_forwarding_combined_reader_is_consistent_with_slicing` violates
this by passing a temporary to `fast_forward_to`.
Fix that.
Fixesscylladb/scylladb#24542Closesscylladb/scylladb#24543
(cherry picked from commit 27f66fb110)
Closesscylladb/scylladb#24548
Token metadata api is initialized before gossiper is started.
get_host_id_map REST endpoint cannot function without the fully
initialized gossiper though. The gossiper is started deep in
the join_cluster call chain, but if we move token_metadata api
initialization after the call it means that no api will be available
during bootstrap. This is not what we want.
Make a simple fix by returning an error from the api if the gossiper is
not initialized yet.
Fixes: #24479Closesscylladb/scylladb#24575
(cherry picked from commit e364995e28)
Closesscylladb/scylladb#24587
cql, schema: Extend name length limit from 48 to 192 bytes
This commit increases the maximum length of names for keyspaces, tables, materialized views, and indexes from 48 to 192 bytes.
The previous 48-bytes limit was inherited from Cassandra 3 for compatibility. However, this validation was removed in Cassandra 4 and 5 (see CASSANDRA-20389)
and some usage scenarios (such as some feature store workflows generating long table names) now depend on this relaxed constraint.
This change brings ScyllaDB's behavior in line with modern Cassandra versions and better supports these use cases.
The new limit of 192 bytes is derived from underlying filesystem limitations to prevent runtime errors when creating directories for table data.
When a new table is created, ScyllaDB generates a directory for its SSTables. The directory name is constructed from the table name, a dash, and a 32-character UUID.
For a CDC-enabled table, an associated log table is also created, which has the suffix `_scylla_cdc_log` appended to its name.
The directory name for this log table becomes the longest possible representation.
Additionally we reserve 15 bytes for future use, allowing for potential future extensions without breaking existing schemas.
To guarantee that directory creation never fails due to exceeding filesystem name limits, the maximum name length is calculated as follows:
255 bytes (common filesystem limit for a path component)
- 32 bytes (for the 32-character UUID string)
- 1 byte (for the '-' separator)
- 15 bytes (for the '_scylla_cdc_log' suffix)
- 15 bytes (reserved for future use)
----------
= 192 bytes (Maximum allowed name length)
This calculation is similar in principle to the one proposed for Cassandra to fix related directory creation failures (see apache/cassandra/pull/4038).
This patch also updates/adds all associated tests to validate the new 192-byte limit.
The documentation has been updated accordingly.
Fixes#4480
Backport 2025.2: The significantly shorter maximum table name length in Scylla compared to Cassandra is becoming a more common issue for users in the latest release.
- (cherry picked from commit a41c12cd85)
- (cherry picked from commit 4577c66a04)
Parent PR: #24500Closesscylladb/scylladb#24603
* github.com:scylladb/scylladb:
cql, schema: Extend name length limit from 48 to 192 bytes
replica: Remove unused keyspace::init_storage()
This commit increases the maximum length of names for keyspaces, tables, materialized views, and indexes from 48 to 192 bytes.
The previous 48-bytes limit was inherited from Cassandra 3 for compatibility. However, this validation was removed in Cassandra 4 and 5 (see CASSANDRA-20389)
and some usage scenarios (such as some feature store workflows generating long table names) now depend on this relaxed constraint.
This change brings ScyllaDB's behavior in line with modern Cassandra versions and better supports these use cases.
The new limit of 192 bytes is derived from underlying filesystem limitations to prevent runtime errors when creating directories for table data.
When a new table is created, ScyllaDB generates a directory for its SSTables. The directory name is constructed from the table name, a dash, and a 32-character UUID.
For a CDC-enabled table, an associated log table is also created, which has the suffix `_scylla_cdc_log` appended to its name.
The directory name for this log table becomes the longest possible representation.
Additionally we reserve 15 bytes for future use, allowing for potential future extensions without breaking existing schemas.
To guarantee that directory creation never fails due to exceeding filesystem name limits, the maximum name length is calculated as follows:
255 bytes (common filesystem limit for a path component)
- 32 bytes (for the 32-character UUID string)
- 1 byte (for the '-' separator)
- 15 bytes (for the '_scylla_cdc_log' suffix)
- 15 bytes (reserved for future use)
----------
= 192 bytes (Maximum allowed name length)
This calculation is similar in principle to the one proposed for Cassandra to fix related directory creation failures (see apache/cassandra/pull/4038).
This patch also updates/adds all associated tests to validate the new 192-byte limit.
The documentation has been updated accordingly.
(cherry picked from commit 4577c66a04)
