* Protect penciller from empty ledger cache updates
which may occur when loading the ledger from the journal, after the ledger has been cleared.
* Score caching and randomisation
The test allkeydelta_journal_multicompact can occasionally fail when a compaction doesn't happen, but then does the next loop. Suspect this is as a result of score caching, randomisation of key grabs for scoring, plus jitter on size boundaries.
Modified test for predictability.
Plus formatting changes
* Avoid small batches
Avoid small batches due to large SQN gaps
* Rationalise tests
Two tests overlaps with the new, much broader, replace_everything/1 test. Ported over any remaining checks of interest and dropped two tests.
* Mas i370 patch d (#383)
* Refactor penciller memory
In high-volume tests on large key-count clusters, so significant variation in the P0031 time has been seen:
TimeBucket PatchA
a.0ms_to_1ms 18554
b.1ms_to_2ms 51778
c.2ms_to_3ms 696
d.3ms_to_5ms 220
e.5ms_to_8ms 59
f.8ms_to_13ms 40
g.13ms_to_21ms 364
h.21ms_to_34ms 277
i.34ms_to_55ms 34
j.55ms_to_89ms 17
k.89ms_to_144ms 21
l.144ms_to_233ms 31
m.233ms_to_377ms 45
n.377ms_to_610ms 52
o.610ms_to_987ms 59
p.987ms_to_1597ms 55
q.1597ms_to_2684ms 54
r.2684ms_to_4281ms 29
s.4281ms_to_6965ms 7
t.6295ms_to_11246ms 1
It is unclear why this varies so much. The time to add to the cache appears to be minimal (but perhaps there is an issue with timing points in the code), whereas the time to add to the index is much more significant and variable. There is also variable time when the memory is rolled (although the actual activity here appears to be minimal.
The refactoring here is two-fold:
- tidy and simplify by keeping LoopState managed within handle_call, and add more helpful dialyzer specs;
- change the update to the index to be a simple extension of a list, rather than any conversion.
This alternative version of the pmem index in unit test is orders of magnitude faster to add - and is the same order of magnitude to check. Anticipation is that it may be more efficient in terms of memory changes.
* Compress SST index
Reduces the size of the leveled_sst index with two changes:
1 - Where there is a common prefix of tuple elements (e.g. Bucket) across the whole leveled_sst file - only the non-common part is indexed, and a function is used to compare.
2 - There is less "indexing" of the index i.e. only 1 in 16 keys are passed into the gb_trees part instead of 1 in 4
* Immediate hibernate
Reasons for delay in hibernate were not clear.
Straight after creation the process will not be in receipt of messages (must wait for the manifest to be updated), so better to hibernate now. This also means the log PC023 provides more accurate information.
* Refactor BIC
This patch avoids the following:
- repeated replacement of the same element in the BIC (via get_kvrange), by checking presence via GET before sing SET
- Stops re-reading of all elements to discover high modified date
Also there appears to have been a bug where a missing HMD for the file is required to add to the cache. However, now the cache may be erased without erasing the HMD. This means that the cache can never be rebuilt
* Use correct size in test results
erts_debug:flat_size/1 returns size in words (i.e. 8 bytes on 64-bit CPU) not bytes
* Don't change summary record
As it is persisted as part of the file write, any change to the summary record cannot be rolled back
* Clerk to prompt L0 write
Simplifies the logic if the clerk request work for the penciller prompts L0 writes as well as Manifest changes.
The advantage now is that if the penciller memory is full, and PUT load stops, the clerk should still be able to prompt persistence. the penciller can therefore make use of dead time this way
* Add push on journal compact
If there has been a backlog, followed by a quiet period - there may be a large ledger cache left unpushed. Journal compaction events are about once per hour, so the performance overhead of a false push should be minimal, with the advantage of clearing any backlog before load starts again.
This is only relevant to riak users with very off/full batch type workloads.
* Extend tests
To more consistently trigger all overload scenarios
* Fix range keys smaller than prefix
Can't make end key an empty binary in this case, as it may be bigger than any keys within the range, but will appear to be smaller.
Unit tests and ct tests added to expose the potential issue
* Tidy-up
- Remove penciller logs which are no longer called
- Get pclerk to only wait MIN_TIMEOUT after doing work, in case there is a backlog
- Remove update_levelzero_cache function as it is unique to handle_call of push_mem, and simple enough to be inline
- Alight testutil slow offer with standard slow offer used
* Tidy-up
Remove pre-otp20 references.
Reinstate the check that the starting pid is still active, this was added to tidy up shutdown.
Resolve failure to run on otp20 due to `-if` sttaement
* Tidy up
Using null rather then {null, Key} is potentially clearer as it is not a concern what they Key is in this case, and removes a comparison step from the leveled_codec:endkey_passed/2 function.
There were issues with coverage in eunit tests as the leveled_pclerk shut down. This prompted a general tidy of leveled_pclerk (remove passing of LoopState into internal functions, and add dialyzer specs.
* Remove R16 relic
* Further testing another issue
The StartKey must always be less than or equal to the prefix when the first N characters are stripped, but this is not true of the EndKey (for the query) which does not have to be between the FirstKey and the LastKey.
If the EndKey query does not match it must be greater than the Prefix (as otherwise it would not have been greater than the FirstKey - so set to null.
* Fix unit test
Unit test had a typo - and result interpretation had a misunderstanding.
* Code and spec tidy
Also look to the cover the situation when the FirstKey is the same as the Prefix with tests.
This is, in theory, not an issue as it is the EndKey for each sublist which is indexed in leveled_tree. However, guard against it mapping to null here, just in case there are dangers lurking (note that tests will still pass without `M > N` guard in place.
* Hibernate on BIC complete
There are three situations when the BIC becomes complete:
- In a file created as part of a merge the BIS is learned in the merge
- After startup, files below L1 learn the block cache through reads that happen to read the block, eventually the while cache will be read, unless...
- Either before/after the cache is complete, it can get whiped by a timeout after a get_sqn request (e.g. as prompted by a journal compaction) ... it will then be re-filled of the back of get/get-range requests.
In all these situations we want to hibernate after the BIC is fill - to reflect the fact that the LoopState should now be relatively stable, so it is a good point to GC and rationalise location of data.
Previously on the the first base was covered. Now all three are covered through the bic_complete message.
* Test all index keys have same term
This works functionally, but is not optimised (the term is replicated in the index)
* Summaries with same index term
If the summary index all have the same index term - only the object keys need to be indexes
* Simplify case statements
We either match the pattern of <<Prefix:N, Suffix>> or the answer should be null
* OK for M == N
If M = N for the first key, it will have a suffix of <<>>. This will match (as expected) a query Start Key of the sam size, and be smaller than any query Start Key that has the same prefix.
If the query Start Key does not match the prefix - it will be null - as it must be smaller than the Prefix (as other wise the query Start Key would be bigger than the Last Key).
The constraint of M > N was introduced before the *_prefix_filter functions were checking the prefix, to avoid issues. Now the prefix is being checked, then M == N is ok.
* Simplify
Correct the test to use a binary field in the range.
To avoid further issue, only apply filter when everything is a binary() type.
* Add test for head_only mode
When leveled is used as a tictacaae key store (in parallel mode), the keys will be head_only entries. Double check they are handled as expected like object keys
* Revert previous change - must support typed buckets
Add assertion to confirm worthwhile optimisation
* Add support for configurable cache multiple (#375)
* Mas i370 patch e (#385)
Improvement to monitoring for efficiency and improved readability of logs and stats.
As part of this, where possible, tried to avoid updating loop state on READ messages in leveled processes (as was the case when tracking stats within each process).
No performance benefits found with change, but improved stats has helped discover other potential gains.
* Query don't copy
Queries the manifest to avoid copying the whole manifest when taking a snapshot of a penciller to run a query.
Change the logging of fold setup in the Bookie to record the actual snapshot time (rather than the uninteresting and fast returning the the function which will request the snapshot).
A little tidy to avoid duplicating the ?MAX_LEVELS macro.
* Clarify log is of snapshot time not fold time
* Updates after review
Previously delete_confirmation was blocked on work_ongoing.
However, if the penciller has a work backlog, work_ongoing may be a recurring problem ... and some files, may remain undeleted long after their use - lifetimes for L0 fails in particular have seen to rise from 10-15s to 5m +.
Letting L0 files linger can have a significant impact on memory. In put-heavy tests (e.g. when testing riak-admin transfers) the memory footprint of a riak node has bene observed peaking more than 80% above normal levels, when compared to using this patch.
This PR allows for deletes to be confirmed even when there is work ongoing, by postponing the updating of the manifest until the manifest is next returned from the clerk.
Co-authored-by: Thomas Arts <thomas.arts@quviq.com>
* Address OTP24 warnings, ct and eunit paths
* Reorg to add OTP 24 support
* Update VOLUME.md
* Correct broken refs
* Update README.md
* CI on all main branches
Co-authored-by: Ulf Wiger <ulf@wiger.net>
Potentially reduce the overheads of scoring each file on every run.
The change also alters the default thresholds for compaction to favour longer runs (which will tend towards greater storage efficiency).
Initial test included for running with recallc, and also transition from retain to recalc.
Moves all logic for startup fold into leveled_bookie - avoid the Inker requiring any direct knowledge about implementation of the Penciller.
Change the penciller check so that it returns current/replaced/missing not just true/false.
Reduce unnecessary penciller checks for non-standard keys that will always be retained - and remove redunandt code.
Expand tests of retain and recover to make sure that compaction on delete is well covered.
Also move the SQN number laong during initial loads - to stop aggressive loop to find starting SQN every file.
Two reasons for logging this:
- to assist in sizing the ledger cache;
- to resolve the mystery when there appear to be no fetches from the penciller (as the penciller does not report fetches from the ledger cache)
Extracting binary from within a binary leaves a reference to the whole of the original binary.
If there are a lot of very large objects received abck toback - this can explode the amount of memory the penciller appears to hold (and gc cannot resolve this).
To dereference from the larger binary, need to do a binary copy
the Journla snapshot is not a true snapshot, in that the active file in the snapshot can still be taking appends. So when getting a snapshot it is necessary to check if folding over the snapshot that the SQN is <= JournalSQN when the snapshot is taken.
Normally consistency of the snapshot is managed as the operation depends on the penciller, and the penciller *is* a snapshot. Not in this case, as the penciller will return true on a sqn check if the pcl SQN is behind the Journal. So the Journal folder, has been given an additionla check to stop at the JournalSQN.
This is perhaps a fault in the pcl check sqn, which should only return true on an exact match? I'm nervous about changing this though, so we have a less pure fix for now.
These logs duplicate information being received from other logs, so reduced to debug.
The long running test needs to change with the LONG_RUNNING macro
Warn at startup if this ratio is high. Not sure how snapshots will perform if there are a lot of ledger cache sin the list. However, it should still work. basic_SUITE/load_count test intended to demonstrate that a large ratio is still functional
Will not lead to immediate run time changes in SST or CDB logs. These log settings will only change once the new files are re-written.
To completely change the log level - a restart of the store is necessary with new startup options.
Test fails as fetching repeated object is too slow.
```Head check took 124301 microseconds checking list of length 5000
Head check took 112286 microseconds checking list of length 5000
Head check took 1336512 microseconds checking list of length 5
2018-12-10T11:54:41.342 B0013 <0.2459.0> Long running task took 260788 microseconds with task of type pcl_head
2018-12-10T11:54:41.618 B0013 <0.2459.0> Long running task took 276508 microseconds with task of type pcl_head
2018-12-10T11:54:41.894 B0013 <0.2459.0> Long running task took 275225 microseconds with task of type pcl_head
2018-12-10T11:54:42.173 B0013 <0.2459.0> Long running task took 278836 microseconds with task of type pcl_head
2018-12-10T11:54:42.477 B0013 <0.2459.0> Long running task took 304524 microseconds with task of type pcl_head```
It taks twice as long to check for one repeated object as it does to check for 5K non-repeated objects
this was previously not na issue as leveled_codec:segment_hash/1 would handle anyhting that could be hashed. This now has to be a tuple, and one with a first element - so corrupted tuples are failing.
Add a guard chekcing for a corrupted tuple, but we only need this when doing journal compaction.
Change user_defined keys to be `retain` as a tag strategy
the skip/retain/recalc handlign was confusing. This removes the switcheroo between leveled_codec and leveled_iclerk when mkaing the decision.
Also now the building of the accumulator is handled efficiently (not using ++ on the list).
Tried to rmeove as much of ?HEAD tag handling from leveled_head - as we want leveled_head to be only concerned with the head manipulation for object tags (?STD, ?RIAK and user-defined).
