systemd unit name of scylla-node-exporter is
scylla-node-exporter.service, not node-exporter.service.
Fixes#8966Closes#8967
(cherry picked from commit f19ebe5709)
Listing /etc/systemd/system/*.mount as ghost file seems incorrect,
since user may want to keep using RAID volume / coredump directory after
uninstalling Scylla, or user may want to upgrade enterprise version.
Also, we mixed two types of files as ghost file, it should handle differently:
1. automatically generated by postinst scriptlet
2. generated by user invoked scylla_setup
The package should remove only 1, since 2 is generated by user decision.
However, just dropping .mount from %files section causes another
problem, rpm will remove these files during upgrade, instead of
uninstall (#8924).
To fix both problem, specify .mount files as "%ghost %config".
It will keep files both package upgrade and package remove.
See scylladb/scylla-enterprise#1780Closes#8810Closes#8924Closes#8959
(cherry picked from commit f71f9786c7)
Commit 5adb8e555c marked the ::feed_hash() and a visitor lambda of
digester::feed_hash() as noexcept. This was quite recklesl as the
appending_hash<>::operator()s called by ::feed_hash() are not all
marked noexcept. In particular, the appending_hash<row>() is not
such and seem to throw.
The original intent of the mentioned commit was to facilitate the
partition_hasher in repair/ code. The hasher itself had been removed
by the 0af7a22c21, so it no longer needs the feed_hash-s to be
noexcepts.
The fix is to inherit noexcept from the called hashers, but for the
digester::feed_hash part the noexcept is just removed until clang
compilation bug #50994 is fixed.
fixes: #8983
tests: unit(dev)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210706153608.4299-1-xemul@scylladb.com>
(cherry picked from commit 63a2fed585)
With strict mode, it could happen that a sstable alone in level 0 is
selected for offstrategy compaction, which means that we could run
into an infinite reshape process.
This is fixed by respecting the offstrategy threshold. Unit test is
added.
Fixes#8573.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20210506181324.49636-1-raphaelsc@scylladb.com>
(cherry picked from commit 8480839932)
Wrong comparison operator is used when checking for overlapping. It
would miss overlapping when last key of a sstable is equal to the first
key of another sstable that comes next in the set, which is sorted by
first key.
Fixes#8531.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
(cherry picked from commit 39ecddbd34)
Fixes#8270
If we have an allocation pattern where we leave large parts of segments "wasted" (typically because the segment has empty space, but cannot hold the mutation being added), we can have a disk usage that is below threshold, yet still get a disk footprint that is over limit causing new segment allocation to stall.
We need to take a few things into account:
1.) Need to include wasted space in the threshold check. Whether or not disk is actually used does not matter here.
2.) If we stall a segment alloc, we should just flush immediately. No point in waiting for the timer task.
3.) Need to adjust the thresholds a bit. Depending on sizes, we should probably consider start flushing once we've used up space enough to be in the last available segment, so a new one is hopefully available by the time we hit the limit.
4.) (v2) Must ensure discard/delete routines are executed. Because we can race with background disk syncs, we may need to
issue segment prunes from end_flush() so we wake up actual file deletion/recycling
5.) (v2) Shutdown must ensure discard/delete is run after we've disabled background task etc, otherwise we might fail waking up replenish and get stuck in gate
6.) (v2) Recycling or deleting segments must be consistent, regardless of shutdown. For same reason as above.
7.) (v3) Signal recycle/delete queues/promise on shutdown (with recognized marker) to handle edge case where we only have a single (allocating) segment in the list, and cannot wake up replenisher in any more civilized way.
Also fix edge case (for tests), when we have too few segment to have an active one (i.e. need flush everything).
New attempt at this, should fix intermittent shutdown deadlocks in commitlog_test.
Closes#8764
* github.com:scylladb/scylla:
commitlog_test: Add test case for usage/disk size threshold mismatch
commitlog_test: Improve test assertion
commitlog: Add waitable future for background sync/flush
commitlog: abort queues on shutdown
commitlog: break out "abort" calls into member functions
commitlog: Do explicit discard+delete in shutdown
commitlog: Recycle or not should not depend on shutdown state
commitlog: Issue discard_unused_segments on segment::flush end IFF deletable
commitlog: Flush all segments if we only have one.
commitlog: Always force flush if segment allocation is waiting
commitlog: Include segment wasted (slack) size in footprint check
commitlog: Adjust (lower) usage threshold
(cherry picked from commit 14252c8b71)
Shutdown must never fail, otherwise it may cause hangs
as seen in https://github.com/scylladb/scylla/issues/8577.
This change wraps the file created in `allocate_segment_ex` in `make_checked_file` so that scylla will abort when failing to write to the commitlog files.
In case other errors are seen during shutdown, just log them and continue with shutting down to prevent scylla from hanging.
Fixes#8577
Test: unit(dev)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closes#8578
* github.com:scylladb/scylla:
commitlog: segment_manager::shutdown: abort on errors
commitlog: allocate_segment_ex: make_checked_file
(cherry picked from commit 48ff641f67)
This was triggered by the test_total_space_limit_of_commitlog dtest.
When it passes a very large commitlog_segment_size_in_mb (1/6th of the
free memory size, in mb), segment_manager constructor limits max_size
to std::numeric_limits<position_type>::max() which is 0xffffffff.
This causes allocate_segment_ex to loop forever when writing the segment
file since `dma_write` returns 0 when the count is unaligned (seen 4095).
The fix here is to select a sligtly small maxsize that is aligned
down to a multiple of 1MB.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20210407121059.277912-1-bhalevy@scylladb.com>
(cherry picked from commit 705f9c4f79)
Backport of 6726fe79b6.
The code was susceptible to use-after-move if both local
and remote updates were going to be sent.
The whole routine for sending view updates is now rewritten
to avoid use-after-move.
Fixes#8830
Tests: unit(release),
dtest(secondary_indexes_test.py:TestSecondaryIndexes.test_remove_node_during_index_build)
Closes#8834
* backport-6726fe7:
view: fix use-after-move when handling view update failures
db,view: explicitly move the mutation to its helper function
db,view: pass base token by value to mutate_MV
The code was susceptible to use-after-move if both local
and remote updates were going to be sent.
The whole routine for sending view updates is now rewritten
to avoid use-after-move.
Refs #8830
Tests: unit(release),
dtest(secondary_indexes_test.py:TestSecondaryIndexes.test_remove_node_during_index_build)
The `apply_to_remote_endpoints` helper function used to take
its `mut` parameter by reference, but then moved the value from it,
which is confusing and prone to errors. Since the value is moved-from,
let's pass it to the helper function as rvalue ref explicitly.
The base token is passed cross-continuations, so the current way
of passing it by const reference probably only works because the token
copying is cheap enough to optimize the reference out.
Fix by explicitly taking the token by value.
This backport fixes the follow issue:
Cassandra stress fails to achieve consistency during replace node operation #8013
without the NODE_OPS_CMD infrastructure.
The commit c82250e0cf (gossip: Allow deferring advertise of local node to be up) which fixes for
During replace node operation - replacing node is used to respond to read queries #7312
is already present in 4.5 branch.
Closes#8703
* github.com:scylladb/scylla:
storage_service: Delay update pending ranges for replacing node
gossip: Add helper to wait for a node to be up
In issue #5021 we noticed that the equality check in Alternator's condition
expressions needs to handle sets differently - we need to compare the set's
elements ignoring their order. But the implementation we added to fix that
issue was only correct when the entire attribute was a set... In the
general case, an attribute can be a nested document, with only some
inner set. The equality-checking function needs to tranverse this nested
document, and compare the sets inside it as appropriate. This is what
we do in this patch.
This patch also adds a new test comparing equality of a nested document with
some inner sets. This test passes on DynamoDB, failed on Alternator before
this patch, and passes with this patch.
Refs #5021Fixes#8514
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210419184840.471858-1-nyh@scylladb.com>
(cherry picked from commit dae7528fe5)
In issue #5021 we noted that Alternator's equality operator needs to be
fixed for the case of comparing two sets, because the equality check needs
to take into account the possibility of different element order.
Unfortunately, we fixed only the equality check operator, but forgot there
is also an inequality operator!
So in this patch we fix the inequality operator, and also add a test for
it that was previously missing.
The implementation of the inequality operator is trivial - it's just the
negation of the equality test. Our pre-existing tests verify that this is
the correct implementation (e.g., if attribute x doesn't exist, then "x = 3"
is false but "x <> 3" is true).
Refs #5021Fixes#8513
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210419141450.464968-1-nyh@scylladb.com>
(cherry picked from commit 50f3201ee2)
When a condition expression (ConditionExpression, FilterExpression, etc.)
checks for equality of two item attributes, i.e., "x = y", and when one of
these attributes was missing we correctly returned false.
However, we also need to return false when *both* attributes are missing in
the item, because this is what DynamoDB does in this case. In other words
an unset attribute is never equal to anything - not even to another unset
attribute. This was not happening before this patch:
When x and y were both missing attributes, Alternator incorrectly returned
true for "x = y", and this patch fixes this case. It also fixes "x <> y"
which should to be true when both x and y are unset (but was false
before this patch).
The other comparison operators - <, <=, >, >=, BETWEEN, were all
implemented correctly even before this patch.
This patch also includes tests for all the two-unset-attribute cases of
all the operators listed above. As usual, we check that these tests pass
on both DynamoDB and Alternator to confirm our new behavior is the correct
one - before this patch, two of the new tests failed on Alternator and
passed on DynamoDB.
Fixes#8511
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210419123911.462579-1-nyh@scylladb.com>
(cherry picked from commit 46448b0983)
This is a follow up change to #8512.
Let's add aio conf file during scylla installation process and make sure
we also remove this file when uninstall Scylla
As per Avi Kivity's suggestion, let's set aio value as static
configuration, and make it large enough to work with 500 cpus.
Closes#8650
Refs: #8713
(cherry picked from commit dd453ffe6a)
On severl instance types in AWS and Azure, we get the following failure
during scylla_io_setup process:
```
ERROR 2021-04-14 07:50:35,666 [shard 5] seastar - Could not setup Async
I/O: Resource temporarily unavailable. The most common cause is not
enough request capacity in /proc/sys/fs/aio-max-nr. Try increasing that
number or reducing the amount of logical CPUs available for your
application
```
We have scylla_prepare:configure_io_slots() running before the
scylla-server.service start, but the scylla_io_setup is taking place
before
1) Let's move configure_io_slots() to scylla_util.py since both
scylla_io_setup and scylla_prepare are import functions from it
2) cleanup scylla_prepare since we don't need the same function twice
3) Let's use configure_io_slots() during scylla_io_setup to avoid such
failure
Fixes: #8587Closes#8512
Refs: #8713
(cherry picked from commit 588a065304)
In commit c82250e0cf (gossip: Allow deferring
advertise of local node to be up), the replacing node is changed to postpone
the responding of gossip echo message to avoid other nodes sending read
requests to the replacing node. It works as following:
1) replacing node does not respond echo message to avoid other nodes to
mark replacing node as alive
2) replacing node advertises hibernate state so other nodes knows
replacing node is replacing
3) replacing node responds echo message so other nodes can mark
replacing node as alive
This is problematic because after step 2, the existing nodes in the
cluster will start to send writes to the replacing node, but at this
time it is possible that existing nodes haven't marked the replacing
node as alive, thus failing the write request unnecessarily.
For instance, we saw the following errors in issue #8013 (Cassandra
stress fails to achieve consistency when only one of the nodes is down)
```
scylla:
[shard 1] consistency - Live nodes 2 do not satisfy ConsistencyLevel (2
required, 1 pending, live_endpoints={127.0.0.2, 127.0.0.1},
pending_endpoints={127.0.0.3}) [shard 0] gossip - Fail to send
EchoMessage to 127.0.0.3: std::runtime_error (Not ready to respond
gossip echo message)
c-s:
java.io.IOException: Operation x10 on key(s) [4c4f4d37324c35304c30]:
Error executing: (UnavailableException): Not enough replicas available
for query at consistency QUORUM (2 required but only 1 alive
```
To solve this problem for older releases without the patch "repair:
Switch to use NODE_OPS_CMD for replace operation", a minimum fix is
implemented in this patch. Once existing nodes learn the replacing node
is in HIBERNATE state, they add the replacing as replacing, but only add
the replacing to the pending list only after the replacing node is
marked as alive.
With this patch, when the existing nodes start to write to the replacing
node, the replacing node is already alive.
Tests: replace_address_test.py:TestReplaceAddress.replace_node_same_ip_test + manual test
Fixes: #8013Closes#8614
(cherry picked from commit e4872a78b5)
Currently, var-lib-scylla.mount may fails because it can start before
MDRAID volume initialized.
We may able to add "After=dev-disk-by\x2duuid-<uuid>.device" to wait for
device become available, but systemd manual says it automatically
configure dependency for mount unit when we specify filesystem path by
"absolute path of a device node".
So we need to replace What=UUID=<uuid> to What=/dev/disk/by-uuid/<uuid>.
Fixes#8279Closes#8681
(cherry picked from commit 3d307919c3)
Currently, unified installer does not apply correct file security context
while copying files, it causes permission error on scylla-server.service.
We should apply default file security context while copying files, using
'-Z' option on /usr/bin/install.
Also, because install -Z requires normalized path to apply correct security
context, use 'realpath -m <PATH>' on path variables on the script.
Fixes#8589Closes#8602
(cherry picked from commit 60c0b37a4c)
Since we have added scylla-node-exporter, we needed to do 'install -d'
for systemd directory and sysconfig directory before copying files.
Fixes#8663Closes#8664
(cherry picked from commit 6faa8b97ec)
When recreating the paging state from an indexed query,
a bunch of panic checks were introduced to make sure that
the code is correct. However, one of the checks is too eager -
namely, it throws an error if the base column type is not equal
to the view column type. It usually works correctly, unless the
base column type is a clustering key with DESC clustering order,
in which case the type is actually "reversed". From the point of view
of the paging state generation it's not important, because both
types deserialize in the same way, so the check should be less
strict and allow the base type to be reversed.
Tests: unit(release), along with the additional test case
introduced in this series; the test also passes
on Cassandra
Fixes#8666Closes#8667
* github.com:scylladb/scylla:
test: add a test case for paging with desc clustering order
cql3: relax a type check for index paging
(cherry picked from commit 593ad4de1e)
run_custom_job() was swallowing all exceptions, which is definitely
wrong because failure in a resharding or reshape would be incorrectly
interpreted as success, which means upper layer will continue as if
everything is ok. For example, ignoring a failure in resharding could
result in a shared sstable being left unresharded, so when that sstable
reaches a table, scylla would abort as shared ssts are no longer
accepted in the main sstable set.
Let's allow the exception to be propagated, so failure will be
communicated, and resharding and reshape will be all or nothing, as
originally intended.
Fixes#8657.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20210515015721.384667-1-raphaelsc@scylladb.com>
(cherry picked from commit 10ae77966c)
The timestamp_type is an int64_t. So, it has to be explicitly
initialized before using it.
This missing inicialization prevented the major compactation
from happening when a time window finishes, as described in #8569.
Fixes#8569
Signed-off-by: Lauro Ramos Venancio <lauro.venancio@incognia.com>
Closes#8590
(cherry picked from commit 15f72f7c9e)
Tracing is created in two steps and is destroyed in two too.
The 2nd step doesn't have the corresponding stop part, so here
it is -- defer tracing stop after it was started.
But need to keep in mind, that tracing is also shut down on
drain, so the stopping should handle this.
Fixes#8382
tests: unit(dev), manual(start-stop, aborted-start)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210331092221.1602-1-xemul@scylladb.com>
(cherry picked from commit 887a1b0d3d)
This is a backport of 8aaa3a7bb8 to <= branch-4.5. The main conflicts were around Benny's reader close series (fa43d7680), but it also turned out that an additional patch (2f1d65ca11) also has to backported to make sure admission on signaling resources doesn't deadlock.
Refs: https://github.com/scylladb/scylla/issues/8493Closes#8558
* github.com:scylladb/scylla:
test: mutation_reader_test: add test_reader_concurrency_semaphore_forward_progress
test: mutation_reader_test: add test_reader_concurrency_semaphore_readmission_preserves_units
reader_concurrency_semaphore: add dump_diagnostics()
reader_permit: always forward resources
test: multishard_mutation_query_test: fuzzy-test: don't consume resource up-front
reader_concurrency_semaphore: make admission conditions consistent
This unit test checks that the semaphore doesn't get into a deadlock
when contended, in the presence of many memory-only reads (that don't
wait for admission). This is tested by simulating the 3 kind of reads we
currently have in the system:
* memory-only: reads that don't pass admission and only own memory.
* admitted: reads that pass admission.
* evictable: admitted reads that are furthermore evictable.
The test creates and runs a large number of these reads in parallel,
read kinds being selected randomly, then creates a watchdog which
kills the test if no progress is being made.
(cherry picked from commit 45d580f056)
This unit test passes a read through admission again-and-again, just
like an evictable reader would be during its lifetime. When readmitted
the read sometimes has to wait and sometimes not. This is to check that
the readmitting a previously admitted reader doesn't leak any units.
(cherry picked from commit cadc26de38)
Allow semaphore related tests to include a diagnostics printout in error
messages to help determine why the test failed.
(cherry picked from commit d246e2df0a)
This commit conceptually reverts 4c8ab10. Said commit was meant to
prevent the scenario where memory-only permits -- those that don't pass
admission but still consume memory -- completely prevent the admission
of reads, possibly even causing a deadlock because a permit might even
blocks its own admission. The protection introduced by said commit
however proved to be very problematic. It made the status of resources
on the permit very hard to reason about and created loopholes via which
permits could accumulate without tracking or they could even leak
resources. Instead of continuing to patch this broken system, this
commit does away with this "protection" based on the observation that
deadlocks are now prevented anyway by the admission criteria introduced
by 0fe75571d9, which admits a read anyway when all the initial count
resources are available (meaning no admitted reader is alive),
regardless of availability of memory.
The benefits of this revert is that the semaphore now knows about all
the resources and is able to do its job better as it is not "lied to"
about resource by the permits. Furthermore the status of a permit's
resources is much simpler to reason about, there are no more loopholes
in unexpected state transitions to swallow/leak resources.
To prove that this revert is indeed safe, in the next commit we add
robust tests that stress test admission on a highly contested semaphore.
This patch also does away with the registered/admitted differentiation
of permits, as this doesn't make much sense anymore, instead these two
are unified into a single "active" state. One can always tell whether a
permit was admitted or not from whether it owns count resources anyway.
(cherry picked from commit caaa8ef59a)
The fuzzy test consumes a large chunk of resource from the semaphore
up-front to simulate a contested semaphore. This isn't an accurate
simulation, because no permit will have more than 1 units in reality.
Furthermore this can even cause a deadlock since 8aaa3a7 as now we rely
on all count units being available to make forward progress when memory
is scarce.
This patch just cuts out this part of the test, we now have a dedicated
unit test for checking a heavily contested semaphore, that does it
properly, so no need to try to fix this clumsy attempt that is just
making trouble at this point.
Refs: #8493
Tests: release(multishard_mutation_query_test:fuzzy_test)
Signed-off-by: Botond Dénes <bdenes@scylladb.com>
Message-Id: <20210429084458.40406-1-bdenes@scylladb.com>
(cherry picked from commit 26ae9555d1)
Migration manager has a function to get a schema (for read or write),
this function queries a peer node and retrieves the schema from it. One
scenario where it can happen is if an old node, queries an old not fixed
index.
This makes a hole through which views that are only adjusted for reading
can slip through.
Here we plug the hole by fixing such views before they are registered.
Closes#8509
(cherry picked from commit 480a12d7b3)
Fixes#8554.
Currently there are two places where we check admission conditions:
`do_wait_admission()` and `signal()`. Both use `has_available_units()`
to check resource availability, but the former has some additional
resource related conditions on top (in `may_proceed()`), which lead to
the two paths working with slightly different conditions. To fix, push
down all resource availability related checks to `has_available_units()`
to ensure admission conditions are consistent across all paths.
(cherry picked from commit d90cd6402c)
Fixes#8363Fixes#8376
Delete segements has two issues when running with size-limited
commit log and strict adherence to said limit.
1.) It uses parallel processing, with deferral. This means that
the disk usage variables it looks at might not be fully valid
- i.e. we might have already issued a file delete that will
reduce disk footprint such that a segment could instead be
recycled, but since vars are (and should) only updated
_post_ delete, we don't know.
2.) It does not take into account edge conditions, when we only
delete a single segment, and this segment is the border segment
- i.e. the one pushing us over the limit, yet allocation is
desperately waiting for recycling. In this case we should
allow it to live on, and assume that next delete will reduce
footprint. Note: to ensure exact size limit, make sure
total size is a multiple of segment size.
if we had an error in recycling (disk rename?), and no elements
are available, we could have waiters hoping they will get segements.
abort the queue (not permanent, but wakes up waiters), and let them
retry. Since we did deletions instead, disk footprint should allow
for new allocs at least. Or more likely, everything is broken, but
we will at least make more noise.
Closes#8372
* github.com:scylladb/scylla:
commitlog: Add signalling to recycle queue iff we fail to recycle
commitlog: Fix race and edge condition in delete_segments
commitlog: coroutinize delete_segments
commitlog_test: Add test for deadlock in recycle waiter
(cherry picked from commit 8e808a56d2)
It is possible that a partition is in cache but is not present in sstables that are underneath.
In such case:
1. cache_flat_mutation_reader will fast forward underlying reader to that partition
2. The underlying reader will enter the state when it's empty and its is_end_of_stream() returns true
3. Previously cache_flat_mutation_reader::do_fill_buffer would try to fast forward such empty underlying reader
4. This PR fixes that
Test: unit(dev)
Fixes#8435Fixes#8411Closes#8437
* github.com:scylladb/scylla:
row_cache: remove redundant check in make_reader
cache_flat_mutation_reader: fix do_fill_buffer
read_context: add _partition_exists
read_context: remove skip_first_fragment arg from create_underlying
read_context: skip first fragment in ensure_underlying
(cherry picked from commit 163f2be277)
When a particular partition exists in at least one sstable, the cache
expects any single-partition query to this partition to return a `partition_start`
fragment, even if the result is empty.
In `time_series_sstable_set::create_single_key_sstable_reader` it could
happen that all sstables containing data for the given query get
filtered out and only sstables without the relevant partition are left,
resulting in a reader which immediately returns end-of-stream (while it
should return a `partition_start` and if not in forwarding mode, a
`partition_end`). This commit fixes that.
We do it by extending the reader queue (used by the clustering reader
merger) with a `dummy_reader` which will be returned by the queue as
the very first reader. This reader only emits a `partition_start` and,
if not in forwarding mode, a `partition_end` fragment.
Fixes#8447.
Closes#8448
(cherry picked from commit 5c7ed7a83f)
The merger could return end-of-stream if some (but not all) of the
underlying readers were empty (i.e. not even returning a
`partition_start`). This could happen in places where it was used
(`time_series_sstable_set::create_single_key_sstable_reader`) if we
opened an sstable which did not have the queried partition but passed
all the filters (specifically, the bloom filter returned a false
positive for this sstable).
The commit also extends the random tests for the merger to include empty
readers and adds an explicit test case that catches this bug (in a
limited scope: when we merge a single empty reader).
It also modifies `test_twcs_single_key_reader_filtering` (regression
test for #8432) because the time where the clustering key filter is
invoked changes (some invocations move from the constructor of the
merger to operator()). I checked manually that it still catches the bug
when I reintroduce it.
Fixes#8445.
Closes#8446
(cherry picked from commit 7ffb0d826b)
The filter passed to `min_position_reader_queue`, which was used by
`clustering_order_reader_merger`, would incorrectly include sstables as
soon as they passed through the PK (bloom) filter, and would include
sstables which didn't pass the PK filter (if they passed the CK
filter). Fortunately this wouldn't cause incorrect data to be returned,
but it would cause sstables to be opened unnecessarily (these sstables
would immediately return eof), resulting in a performance drop. This commit
fixes the filter and adds a regression test which uses statistics to
check how many times the CK filter was invoked.
Fixes#8432.
Closes#8433
(cherry picked from commit 3687757115)
compound set isn't overriding create_single_key_sstable_reader(), so
default implementation is always called. Although default impl will
provide correct behavior, specialized ones which provides better perf,
which currently is only available for TWCS, were being ignored.
compound set impl of single key reader will basically combine single key
readers of all sets managed by it.
Fixes#8415.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20210406205009.75020-1-raphaelsc@scylladb.com>
(cherry picked from commit 8e0a1ca866)