All reader are soon going to require a valid permit, so make sure we
have a valid permit which we can pass to the underlying reader when
creating it. This means `row_cache::make_reader()` now also requires
a permit to be passed to it.
All reader are soon going to require a valid permit, so make sure we
have a valid permit which we can pass to the delegate reader when
creating it. This means `memtable::make_flat_reader()` now also requires
a permit to be passed to it.
Internally the permit is stored in `scanning_reader`, which is used both
for flushes and normal reads. In the former case a permit is not
required.
Now that the most prevalent users (range scan and single partition
reads) all pass valid permits we require all users to do so and
propagate the permit down towards `make_sstable_reader()`. The plan is
to use this permit for restricting the sstable readers, instead of the
semaphore the table is configured with. The various
`make_streaming_*reader()` overloads keep using the internal semaphores
as but they also create the permit before the read starts and pass it to
`make_sstable_reader()`.
We want to move away from the current practice of selecting the relevant
read concurrency semaphore inside `table` and instead want to pass it
down from `database` so that we can pass down a semaphore that is
appropriate for the class of the query. Use the recently created
`query_class_config` struct for this. This is added as a parameter to
`data_query`, `mutation_query` and propagated down to the point where we
create the `querier` to execute the read. We are already propagating
down a parameter down the same route -- max_memory_reverse_query --
which also happens to be part of `query_class_config`, so simply replace
this parameter with a `query_class_config` one. As the lower layers are
not prepared for a semaphore passed from above, make sure this semaphore
is the same that is selected inside `table`. After the lower layers are
prepared for a semaphore arriving from above, we will switch it to be
the appropriate one for the class of the query.
Mutation sources will soon require a valid permit so make sure we have
one and pass it to the mutation sources when creating the underlying
readers.
For now, pass no_reader_permit() on call sites, deferring the obtaining
of a valid permit to later patches.
In order to add tracing to places where it can be useful,
e.g. materialized view updates and hinted handoff, tracing state
is propagated to all applicable call sites.
After commit 88d2486fca, removal of shared SSTables is not atomic anymore.
They can be first removed from the list of shared SSTables and only later be
removed from the SSTable set. That list is used to filter out shared SSTables
from regular compaction candidates.
So it can happen that regular compaction pick up a shared SSTable as candidate
after it was removed from that list but before it was removed from the set.
To fix this, let's only remove a shared SSTable from that aforementioned list
after it was successfully removed from the SSTable set, so that a shared
SSTable cannot be selected for regular compaction anymore.
Fixes#6439.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20200512175224.114487-1-raphaelsc@scylladb.com>
"
We inherited from Origin a `caching` table parameter. It's a map of named caching parameters. Before this PR two caching parameters were expected: `keys` and `rows_per_partition`. So far we have been ignoring them. This PR adds a new caching parameter called `enabled` which can be set to `true` or `false` and controls the usage of the cache for the table. By default, it's set to `true` which reflects Scylla behavior before this PR.
This new capability is used to disable caching for CDC Log table. It is desirable because CDC Log entries are not expected to be read often. They also put much more pressure on memory than entries in Base Table. This is caused by the fact that some writes to Base Table can override previous writes. Every write to CDC Log is unique and does not invalidate any previous entry.
Fixes#6098Fixes#6146
Tests: unit(dev, release), manual
"
* haaawk-dont_cache_cdc:
cdc: Don't cache CDC Log table
table: invalidate disabled cache on memtable flush
table: Add cache_enabled member function
cf_prop_defs: persist caching_options in schema
property_definitions: add get that returns variant
feature: add PER_TABLE_CACHING feature
caching_options: add enabled parameter
Input SSTables of resharding is deleted at the coordinator shard, not at the
shards they belong to.
We're not acquiring deletion semaphore before removing those input SSTables
from the SSTable set, so it could happen that resharding deletes those
SSTables while another operation like snapshot, which acquires the semaphore,
find them deleted.
Let's acquire the deletion semaphore so that the input SSTables will only
be removed from the set, when we're certain that nobody is relying on their
existence anymore.
Now resharding will only delete input SStables after they're safely removed
from the SSTable set of all shards they belong to.
unit: test(dev).
Fixes#6328.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20200507233636.92104-1-raphaelsc@scylladb.com>
The patch implements:
- /storage_service/auto_compaction API endpoint
- /column_family/autocompaction/{name} API endpoint
Those APIs allow to control and request the status of background
compaction jobs for the existing tables.
The implementation introduces the table::_compaction_disabled_by_user.
Then the CompactionManager checks if it can push the background
compaction job for the corresponding table.
New members
===
table::enable_auto_compaction();
table::disable_auto_compaction();
bool table::is_auto_compaction_disabled_by_user() const
Test
===
Tests: unit(sstable_datafile_test autocompaction_control_test), manual
$ ninja build/dev/test/boost/sstable_datafile_test
$ ./build/dev/test/boost/sstable_datafile_test --run_test=autocompaction_control_test -- -c1 -m2G --overprovisioned --unsafe-bypass-fsync 1 --blocked-reactor-notify-ms 2000000
The test tries to submit a compaction job after playing
with autocompaction control table switch. However, there is
no reliable way to hook pending compaction task. The code
assumed that with_scheduling_group() closure will never
preempt execution of the stats check.
Revert
===
Reverts commit c8247ac. In previous version the execution
sometimes resulted into the following error:
test/boost/sstable_datafile_test.cc(1076): fatal error: in "autocompaction_control_test":
critical check cm->get_stats().pending_tasks == 1 || cm->get_stats().active_tasks == 1 has failed
This version adds a few sstables to the cf, starts
the compaction and awaits until it is finished.
API change
===
- `/column_family/autocompaction/` always returned `true` while answering to the question: if the autocompaction disabled (see https://github.com/scylladb/scylla-jmx/blob/master/src/main/java/org/apache/cassandra/db/ColumnFamilyStore.java#L321). now it answers to the question: if the autocompaction for specific table is enabled. The question logic is inverted. The patch to the JMX is required. However, the change is decent because all old values were invalid (it always reported all compactions are disabled).
- `/column_family/autocompaction/` got support for POST/DELETE per table
Fixes
===
Fixes#1488Fixes#1808Fixes#440
Signed-off-by: Ivan Prisyazhnyy <ivan@scylladb.com>
Reviewed-by: Glauber Costa <glauber@scylladb.com>
"
Garbage collected SSTables, created by incremental compaction process,
are being added to the SSTable set using a function that invalidates
row cache using the range of the SSTable itself. That's incorrect
because data in GC SSTables come from preexisting SSTables in set,
meaning the state of data isn't changed and so no need for
invalidation at all. Incorrect invalidation like this is a source of
read performance issues. This problem is fixed by including GC
SSTables to the descriptor which is used to specify changes to the
SSTable set, which is the correct thing to do given that a midway
failure could leave the set in an incorrect state.
Fixes#5956.
Fixes#6275.
tests: unit(dev)
"
* 'fix_issue_5956_v4' of github.com:raphaelsc/scylla:
sstables/compaction: Don't invalidate row cache when adding GC SSTable to SSTable set
sstables/compaction: Change meaning of compaction_completion_desc input and output fields
sstables/compaction: Clean up code around garbage_collected_sstable_writer
We must unregister the monitor upon destruction to prevent use-after-free
from `compaction_backlog_tracker::backlog` path.
This is similar to ~compaction_read_monitor as implemented
in commit ca284174d0Fixes#6385
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20200506214419.569655-1-bhalevy@scylladb.com>
table::update_cache has two branches of its logic.
One when caching is enabled and the other when it's
disabled. This patch adds unconditional cache invalidation
to the second (disabled caching) branch.
This is done for two purposes. First and foremost, it gives
the guarantee that when we enable the cache later it will be in
the right state and will be ready for usage. This is because
any memtable flush that would logically invalidate the cache,
actually physically does that too now. An additional benefit of this
change is that disabled cache will be cleared during the next
memtable flush that will happen after turning the switch off.
Previously, the cache would also be emptied but it would take
more time before all its elements are removed by eviction.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
input_sstables is renamed to old_sstables and is about old SSTables that should be
deleted and removed from the SSTable set.
output_sstables is renamed to new_sstables and is about new SSTable that should be
added to the SSTable set, replacing the old ones.
This will allow us, for example, to add auxiliary SSTables to SSTable set using
the same call which replaces output SSTables by input SSTables in compaction.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Loading SSTables from the main directory is possible, to be compatible with
Cassandra, but extremely dangerous and not recommended.
From the beginning, we recommend using an separate, upload/ directory.
In all this time, perhaps due to how the feature's usefulness is reduced
in Cassandra due to the possible races, I have never seen anyone coming
from Cassandra doing procedures involving refresh at all.
Loading SSTables from the main directory forces us to disable writes to
the table temporarily until the SSTables are sorted out. If we get rid of
this, we can get rid of the disabling of the writes as well.
We can't do it now because if we want to be nice to the odd user that may
be using refresh through the main directory without our knowledge we should
at least error out.
This patch, then, does that: it errors out if SSTables are found in the main
directory. It will not proceed with the refresh, and direct the user to the
upload directory.
The main loop in reshuffle_sstables is left in place structurally for now, but
most of it is gone. The test for is is deleted.
After a period of deprecation we can start ignoring these SSTables and get rid
of the lock.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Message-Id: <20200429144511.13681-1-glauber@scylladb.com>
A writer is destroyed just before consume_in_thread returns, since the
adapter takes ownership of it.
The problem is that a monitor can keep a reference to the a
writer_offset_tracker that is owned by that writer.
The monitor is accessed periodically via
backlog_controller::_update_timer. This means we have to deregister
from the list of ongoing writes before the writer is destroyed.
If the write fails, the deregistration happens in write_failed, but it
is currently called after the writer is destroyed.
This patch moves the call to write_failed to the writer destructor as
I could not find a convenient location to put it.
Since the writer is destroyed in consume_in_thread, we could call it
there, but then we also have to update consume.
The is a similar problem with the case where the sstable is written
correctly. That will be fixed in the next patch.
Fixes#6221.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Only database_sstable_write_monitor needs it so far, but the call
needs to be moved earlier, which requires calling it in code paths
that don't know about database_sstable_write_monitor.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
There's no indication that data needed for generating view updates
from staging sstables is going to be immediately useful for the
user, and a large amount of it can push hot rows out of the cache,
thus deteriorating performance.
Fixes#6233
Tests: unit(dev)
It is currently not possible to wrap the view_updating_consumer in an
std::optional. I intend to do it to allow for compactions to optionally
generate view updates.
The reason for that is that view_updating_consumer has a reference as a
member, which makes the move assignment constructor not be implicitly
generated.
This patch fixes it by keeping a pointer instead of a reference.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Message-Id: <20200421123648.8328-1-glauber@scylladb.com>
The io_priority parameter used when generating view updates from
streaming is used by the sstable reader, so it should use the I/O priority
for streaming *read* operations, not streaming *write* operations.
Fixes#6231
Tests: unit(dev)
There is no reason to read a single SSTable at a time from the staging
directory. Moving SSTables from staging directory essentially involves
scanning input SSTables and creating new SSTables (albeit in a different
directory).
We have a mechanism that does that: compactions. In a follow up patch, I
will introduce a new specialization of compaction that moves SSTables
from staging (potentially compacting them if there are plenty).
In preparation for that, some signatures have to be changed and the
view_updating_consumer has to be more compaction friendly. Meaning:
- Operating with an sstable vector
- taking a table reference, not a database
Because this code is a bit fragile and the reviewer set is fundamentally
different from anything compaction related, I am sending this separately
* glommer-view_build:
staging: potentially read many SSTables at the same time
view_build_test: make sure it works with smp > 1
There is no reason to read a single SSTable at a time from the staging
directory. Moving SSTables from staging directory essentially involves
scanning input SSTables and creating new SSTables (albeit in a different
directory).
We have a mechanism that does that: compactions. In a follow up patch, I
will introduce a new specialization of compaction that moves SSTables
from staging (potentially compacting them if there are plenty).
In preparation for that, some signatures have to be changed and the
view_updating_consumer has to be more compaction friendly. Meaning:
- Operating with an sstable vector
- taking a table reference, not a database
Because this code is a bit fragile and the reviewer set is fundamentally
different from anything compaction related, I am sending this separately
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Rename inherited metrics cas_propose and cas_commit
to cas_accept and cas_learn respectively.
A while ago we made a decision to stick to widely accepted
terms for Paxos rounds: prepare, accept, learn. The rest
of the code is using these terms, so rename the metrics
to avoid confusion/technical debt.
While at it, rename a few internal methods and functions.
Fixes#6169
Message-Id: <20200414213537.129547-1-kostja@scylladb.com>
This reverts commit 1c444b7e1e. The test
it adds sometimes fails as follows:
test/boost/sstable_datafile_test.cc(1076): fatal error: in "autocompaction_control_test":
critical check cm->get_stats().pending_tasks == 1 || cm->get_stats().active_tasks == 1 has failed
Ivan is working on a fix, but let's revert this commit to avoid blocking
next promotion failing from time to time.
This patch adds API endpoint /column_family/autocompaction/{name}
that listen to GET and POST requests to pick and control table
background compactions.
To implement that the patch introduces "_compaction_disabled_by_user"
flag that affects if CompactionManager is allowed to push background
compactions jobs into the work.
It introduces
table::enable_auto_compaction();
table::disable_auto_compaction();
bool table::is_auto_compaction_disabled_by_user() const
to control auto compaction state.
Fixes#1488Fixes#1808Fixes#440
Tests: unit(sstable_datafile_test autocompaction_control_test), manual
There is no reason why the table code has to be aware of the efforts of
rewriting (cleanup, scrub, upgrade) an SSTable versus compacting it.
Rewrite is special, because we need to do it one SSTable at a time,
without lumping it together. However, the compaction manager is totally
capable of doing that itself. If we do that, the special
"table::rewrite_sstables" can be killed.
This code would maybe be better off as a thread, where we wouldn't need
to keep state. However there are some methods like maybe_stop_on_error()
that expect a future so I am leaving this be for now. This is a cleanup
that can be done later.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Message-Id: <20200401162722.28780-2-glauber@scylladb.com>
This removes the need to include reactor.hh, a source of compile
time bloat.
In some places, the call is qualified with seastar:: in order
to resolve ambiguities with a local name.
Includes are adjusted to make everything compile. We end up
having 14 translation units including reactor.hh, primarily for
deprecated things like reactor::at_exit().
Ref #1
There are many differences between resharding and compaction that are
artificial, arising more from the way we ended up implementing it than
necessity. This patch attempts to pass the creator and replacer functions
through the compaction_descriptor.
There is a difference between the creator function for resharding and
regular compaction: resharding has to pass the shard number on behalf
of which the SSTable is created. However regular compactions can just
ignore this. No need to have a special path just for this.
After this is done, the constructor for the compaction object can be
greatly simplified. In further patches I intend to simplify it a bit
further, but some more cleanup has to happen first.
To make that happen we have to construct a compaction_descriptor object
inside the resharding function. This is temporary: resharding currently
works with a descriptor, but at some point that descriptor is lost and
broken into pieces to be passed to this function. The overarching goal
of this work is exactly to be able to keep that descriptor for as long
as possible, which should simplify things a lot.
Callers are patched, but there are plenty for sstable_datafile_test.cc.
For their benefit, a helper function is provided to keep the previous
signature (test only).
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Before this patch, when db/view/view.hh was modified, 89 source files had to
be recompiled. After this patch, this number is down to 5.
Most of the irrelevant source files got view.hh by including database.hh,
which included view.hh just for the definition of statistics. So in this
patch we split the view statistics to a separate header file, view_stats.hh,
and database.hh only includes that. A few source files which included
only database.hh and also needed view.hh (for materialized-view related
functions) now need to include view.hh explicitly.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20200319121031.540-1-nyh@scylladb.com>
View updates sent as part of the view building process should never
be ignored, but fd49fd7 introduced a bug which may cause exactly that:
the updates are mistakenly sent to background, so the view builder
will not receive negative feedback if an update failed, which will
in turn not cause a retry. Consequently, view building may report
that it "finished" building a view, while some of the updates were
lost. A simple fix is to restore previous behaviour - all updates
triggered by view building are now waited for.
Fixes#6038
Tests: unit(dev),
dtest: interrupt_build_process_with_resharding_low_to_half_test
Currently, launching view updates as an asynchronous background job
is done via not waiting for mutate_MV() future in
table::generate_and_propagate_view_updates. That has a big downside,
since mutate_MV() handles *all* view updates for *all* views of a table,
so it's not possible to wait for each view independently.
Per-view granularity is required in order to implement synchronous
view updates of local views - because then we'll synchronously
wait for all views that write to a local node (due to having a matching
partition key with the base), while remote view updates will still
be sent asynchronously.
In order to do that, instead of not waiting for mutate_MV,
we do wait for it properly, but instead launch the asynchronous,
unwaited-for futures inside mutate_MV.
Effectively that means no changes for view updates so far - all updates
will be fired in the background. Later, another patch will introduce
a way to wait for selected updates to finish.
Regular compaction relies on compaction manager to run compaction jobs
until compaction strategy is satisfied. Resharding, on the other hand,
is an one-off operation which runs only once in compaction manager,
and leave the sstable set in such a way that the strategy is very
likely unsatisfied. We need to trigger regular compaction whenever
a resharding job replaces a shared sstable by an unshared sstable,
so that compaction will not fall way behind due to lots of new sstables
created by resharding process.
Fixes#5262.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20200217144946.20338-1-raphaelsc@scylladb.com>
"
This set cleans sstable_writer_config and surrounding sstables
code from using global storage_ and feature_ service-s and database
by moving the configuration logic onto sstables_manager (that
was supposed to do it since eebc3701a5).
Most of the complexity is hidden around sstable_writer_config
creation, this set makes the sstables_manager create this object
with an explicit call. All the rest are consequences of this change.
Tests: unit(debug), manual start-stop
"
* 'br-clean-sstables-manager-2' of https://github.com/xemul/scylla:
sstables: Move get_highest_supported_format
sstables: Remove global get_config() helper
sstables: Use manager's config() in .new_sstable_component_file()
sstable_writer_config: Extend with more db::config stuff
sstables_manager: Don't use global helper to generate writer config
sstable_writer_config: Sanitize out some features fields initialization
sstable_writer_config: Factor out some field initialization
sstables: Generate writer config via manager only
sstables: Keep reference on manager
test: Re-use existing global sstables_manager
table: Pass sstable_writer_config into write_memtable_to_sstable
"
Timeouts defaulted to `db::no_timeout` are dangerous. They allow any
modifications to the code to drop timeouts and introduce a source of
unbounded request queue to the system.
This series removes the last such default timeouts from the code. No
problems were found, only test code had to be updated.
tests: unit(dev)
"
* 'no-default-timeouts/v1' of https://github.com/denesb/scylla:
database: database::query*(), database::apply*(): remove default timeouts
database: table::query(): remove default timeout
mutation_query: data_query(): remove default timeout
mutation_query: mutation_query(): remove default timeout
multishard_mutation_query: query_mutations_on_all_shards(): remove default timeout
reader_concurrency_semaphore: wait_admission(): remove default timeout
utils/logallog: run_when_memory_available(): remove default timeout
If the reversing requires more memory than the limit, the read is
aborted. All users are updated to get a meaningful limit, from the
respective table object, with the exception of tests of course.
The global get_highest_supported_format helper and its declaration
are scattered all over the code, so clean this up and prepare the
ground for moving _sstables_format from the storage_service onto
the sstables_manager (not this set).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The sstable_writer_config creation looks simple (just declare
the struct instance) but behind the scenes references storage
and feature services, messes with database config, etc.
This patch teaches the sstables_manager generate the writer
config and makes the rest of the code use it. For future
safety by-hands creation of the sstable_writer_config is
prohibited.
The manager is referenced through table-s and sstable-s, but
two existing sstables_managers live on database object, and
table-s and sstable-s both live shorter than the database,
this reference is save.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The latter creates the config by hands, but the plan is to
create it via sstables_manager. Callers of this helper are the
final frontiers where the manager will be safely accessible.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Row cache needs to be invalidated whenever data in sstables changes. Cleanup removes
data from sstables which doesn't belong to the node anymore, which means cache must
be invalidated on cleanup.
Currently, stale data can be returned when a node re-owns ranges which data are still
stored in the node's row cache, because cleanup didn't invalidate the cache.
To prevent data that belongs to the node from being purged from the row cache, cleanup
will only invalidate the cache with a set of token ranges that will not overlap with
any of ranges owned by the node.
update_cluster_layout_tests.py:TestUpdateClusterLayout.simple_decommission_node_2_test
now passes.
Fixes#4446.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
This descriptor contain all information needed for table to be properly
updated on compaction completion. A new member will be added to it soon,
which will store ranges to be invalidated in row cache on behalf of
cleanup compaction.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
" from Botond
Nodetool scrub rewrites all sstables, validating their data. If corrupt
data is found the scrub is aborted. If the skip-corrupted flag is set,
corrupt data is instead logged (just the keys) and skipped.
The scrubbing algorithm itself is fairly simple, especially that we
already have a mutation stream validator that we can use to validate the
data. However currently scrub is piggy-backed on top of cleanup
compaction. To implement this flag, we have to make scrub a separate
compaction type and propagate down the flag. This required some
massaging of the code:
* Add support for more than two (cleanup or not) compaction types.
* Allow passing custom options for each compaction type.
* Allow stopping a compaction without the manager retrying it later.
Additionally the validator itself needed some changes to allow different
ways to handle errors, as needed by the scrub.
Fixes: #5487
* https://github.com/denesb/nodetool-scrub-skip-corrupted/v7:
table: cleanup_sstables(): only short-circuit on actual cleanup
compaction: compaction_type: add Upgrade
compaction: introduce compaction_options
compaction: compaction_descriptor: use compaction options instead of
cleanup flag
compaction_manager: collect all cleanup related logic in
perform_cleanup()
sstables: compaction_stop_exception: add retry flag
mutation_fragment_stream_validator: split into low-level and
high-level API
compaction: introduce scrub_compaction
compaction_manager: scrub: don't piggy-back on upgrade_sstables()
test: sstable_datafile_test: add scrub unit test