* Add eqwalizer and clear for codec & sst
The eqwalizer errors highlighted the need in several places for type clarification.
Within tests there are some issue where a type is assumed, and so ignore has been used to handle this rather than write more complex code to be explicit about the assumption.
The handling of arrays isn't great by eqwalizer - to be specific about the content of array causes issues when initialising an array. Perhaps a type (map maybe) where one can be more explicit about types might be a better option (even if there is a minimal performance impact).
The use of a ?TOMB_COUNT defined option complicated the code much more with eqwalizer. So for now, there is no developer option to disable ?TOMB_COUNT.
Test fixes required where strings have been used for buckets/keys not binaries.
The leveled_sst statem needs a different state record for starting when compared to other modes. The state record has been divided up to reflect this, to make type management easier. The impact on performance needs to be tested.
* Update ct tests to support binary keys/buckets only
* Eqwalizer for leveled_cdb and leveled_tictac
As array is used in leveled_tictac - there is the same issue as with leveled_sst
* Remove redundant indirection of leveled_rand
A legacy of pre-20 OTP
* Morde modules eqwalized
ebloom/log/util/monitor
* Eqwalize further modules
elp eqwalize leveled_codec; elp eqwalize leveled_sst; elp eqwalize leveled_cdb; elp eqwalize leveled_tictac; elp eqwalize leveled_log; elp eqwalize leveled_monitor; elp eqwalize leveled_head; elp eqwalize leveled_ebloom; elp eqwalize leveled_iclerk
All concurrently OK
* Refactor unit tests to use binary() no string() in key
Previously string() was allowed just to avoid having to change all these tests. Go through the pain now, as part of eqwalizing.
* Add fixes for penciller, inker
Add a new ?IS_DEF macro to replace =/= undefined.
Now more explicit about primary, object and query keys
* Further fixes
Need to clarify functions used by runner - where keys , query keys and object keys are used
* Further eqwalisation
* Eqwalize leveled_pmanifest
Also make implementation independent of choice of dict - i.e. one can save a manifest using dict for blooms/pending_deletions and then open a manifest with code that uses a different type. Allow for slow dict to be replaced with map.
Would not be backwards compatible though, without further thought - i.e. if you upgrade then downgrade.
Redundant code created by leveled_sst refactoring removed.
* Fix backwards compatibility issues
* Manifest Entry to belong to leveled_pmanifest
There are two manifests - leveled_pmanifest and leveled_imanifest. Both have manifest_entry() type objects, but these types are different. To avoid confusion don't include the pmanifest manifest_entry() within the global include file - be specific that it belongs to the leveled_pmanifest module
* Ignore elp file - large binary
* Update src/leveled_pmem.erl
Remove unnecessary empty list from type definition
Co-authored-by: Thomas Arts <thomas.arts@quviq.com>
---------
Co-authored-by: Thomas Arts <thomas.arts@quviq.com>
* Add performance/profiling test
Add test to perf_SUITE to do performance tests and also profile different activities in leveled.
This can then be used to highlight functions with unexpectedly high execution times, and prove the impact of changes.
Switch between riak_ctperf and riak_fullperf to change from standard test (with profile option) to full-scale performance test
* Change shape of default perfTest
* Refactor SST
Compare and contrast profile for guess, before and after refactor:
pre
```
lists:map_1/2 313370 2.33 32379 [ 0.10]
lists:foldl_1/3 956590 4.81 66992 [ 0.07]
leveled_sst:'-expand_list_by_pointer/5-fun-0-'/4 925020 6.13 85318 [ 0.09]
erlang:binary_to_term/1 3881 8.55 119012 [ 30.67]
erlang:'++'/2 974322 11.55 160724 [ 0.16]
lists:member/2 4000180 15.00 208697 [ 0.05]
leveled_sst:find_pos/4 4029220 21.01 292347 [ 0.07]
leveled_sst:member_check/2 4000000 21.17 294601 [ 0.07]
-------------------------------------------------- -------- ------- ------- [----------]
Total: 16894665 100.00% 1391759 [ 0.08]
```
post
```
lists:map_1/2 63800 0.79 6795 [ 0.11]
erlang:term_to_binary/1 15726 0.81 6950 [ 0.44]
lists:keyfind/3 180967 0.92 7884 [ 0.04]
erlang:spawn_link/3 15717 1.08 9327 [ 0.59]
leveled_sst:'-read_slots/5-fun-1-'/8 31270 1.15 9895 [ 0.32]
gen:do_call/4 7881 1.31 11243 [ 1.43]
leveled_penciller:find_nextkey/8 180936 2.01 17293 [ 0.10]
prim_file:pread_nif/3 15717 3.89 33437 [ 2.13]
leveled_sst:find_pos/4 4028940 17.85 153554 [ 0.04]
erlang:binary_to_term/1 15717 51.97 447048 [ 28.44]
-------------------------------------------------- ------- ------- ------ [----------]
Total: 6704100 100.00% 860233 [ 0.13]
```
* Update leveled_penciller.erl
* Mas d31 nhskv16sstpcl (#426)
Performance updates to leveled:
- Refactoring of pointer expansion when fetching from leveled_sst files to avoid expensive list concatenation.
- Refactoring of leveled_ebloom to make more flexible, reduce code, and improve check time.
- Refactoring of querying within leveled_sst to reduce the number of blocks that need to be de-serialised per query.
- Refactoring of the leveled_penciller's query key comparator, to make use of maps and simplify the filtering.
- General speed-up of frequently called functions.
* Add compression controls (#417)
* Add compression controls
Add configuration options to allow for a compression algorithm of `none` to disable compression altogether. Also an option to change the point in the LSM tree when compression is applied.
* Handle configurable defaults consistently
Move them into leveled.hrl. This forces double-definitions to be resolved.
There are some other constants in leveled_bookie that are relevant outside of leveled_bookie. These are all now in the non-configurable startup defaults section.
* Clarify referred-to default is OTP not leveled
* Update leveled_bookie.erl
Handle xref issue with eunit include
* 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
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).
During EQC testing it was found that snapshots are still usable even
if the bookie process crashes. This change has snapshots monitor the
bookie and close when the bookie process dies.
Initial commit to add head_only mode to leveled. This allows leveled to receive batches of object changes, but where those objects exist only in the Penciller's Ledger (once they have been persisted within the Ledger).
The aim is to reduce significantly the cost of compaction. Also, the objects ar enot directly accessible (they can only be accessed through folds). Again this makes life easier during merging in the LSM trees (as no bloom filters have to be created).
Previouslythe tinybloom was used within the SST file as an extra check to remove false fetches.
However the SST already has a low FPR check in the slot_index. If the newebloom was used (which is no longer per slot, but per sst), this can be shared with the penciller and then the penciller could use it and avoid the message pass.
the message pass may be blocked by a 2i query or a slot fetch request for a merge. So this should make performance within the Penciller snappier.
This is as a result of taking sst_timings within a volume test - where there was an average of + 100microsecs for each level that was dropped down. Given the bloom/slot checks were < 20 microsecs - there seems to be some further delay.
The bloom is a binary of > 64 bytes - so passing it around should not require a copy.
Compression can be switched between LZ4 and zlib (native).
The setting to determine if compression should happen on receipt is now a macro definition in leveled_codec.
With basic ct test.
Doesn't currently prove expiry of index. Doesn't prove ability to find
segments.
Assumes that either "all" buckets or a special list of buckets require
indexing this way. Will lead to unexpected results if the same bucket
name is used across different Tags.
The format of the index has been chosen so that hopeully standard index
features can be used (e.g. return_terms).
When running a load of mainly 2i queries, there is a huge cost in the
previous snapshot code. The time taken to create a clone of the
Penciller (duplicating all the LoopState) varied between 1 and 200ms
depedning on the size of the LoopState.
For 2i queries, most of that LoopState was then being thrown away after
running the query against the levelzero_cache. This was taking < 1ms on
average. It would be better to avoid the o(100)ms of CPU burning and
block for o(1)ms - so th eorder of events have been changed ot filter
first so only the small part of the LoopState actually required is
copied to the clone.
Under assumption that it generates less GC noise (based on
micro-benchmark in leveled_tree eunit testing).
Note to confirm, needed to swap around the test order, and this showed
less collections in each position for skpl - and a < 10% performance hit
Going to abandond this branch for now. The change is beoming
excessively time consuming, and it is not clear that a smaller change
might not achieve more of the objectives.
All this is broken - but perhaps could get picke dup another day.
This is desirable to add back in going forward, but wasn't implemented
in a safe or clear way.
The way the bloom was or was not on the LoopState was clumsy, and it got
persisted in multiple places without a CRC check.
Intention to implement back in wherby it is requested on-demand by the
Penciller, and then the SFT worker lifts it off disk and CRC checks it.
So it is never on the SFT LoopState. Also it will be easier to control
the logic over which levels have the bloom in the Penciller.
This allows for deleted journals to be retained for a period (the
waste_retnetion_period). The idea being that a backup strategy can
ensure that all journals are backed up, even ones created and removed
from within a backup period - so that any restore pont is possible.
This is also a pre-cursor to removing some of the PromptDelete
complexity from the Inker Clerk - all compactions can prompt deletion as
deletion is now deferred.
There were issues with how the Penciller behaves under ehavy write
pressure - most particularly where there are a large number of keys per
update (i.e. 2i heavy objects). Most immediately the attempt to chekc
whether the l0 file was ready slowed down the process of producing the
L0 file - so back-pressure created more back-pressure.
Going forward want to alter this most significantly as also the work
queue can build up unsustainably. there needs to be some pausing
prompted by the bookie on 'returned', and the use of 'returend when the
work queue exceeds a threshold.
Changes the stratup otpions to a prolist to make it easier to get
environment variables as default.
Tried application:start - and completely baffled as to how to get this
to work.
