* fix(influxd): update xxhash, avoid stringtoslicebyte in cache (#578)
* fix(influxd): update xxhash, avoid stringtoslicebyte in cache
This commit does 3 things:
* it updates xxhash from v1 to v2; v2 includes a assembly arm version of
Sum64
* it changes the cache storer to write with a string key instead of a
byte slice. The cache only reads the key which WriteMulti already has
as a string so we can avoid a host of allocations when converting back
and forth from immutable strings to mutable byte slices. This includes
updating the cache ring and ring partition to write with a string key
* it updates the xxhash for finding the cache ring partition to use
Sum64String which uses unsafe pointers to directly use a string as a
byte slice since it only reads the string. Note: this now uses an
assembly version because of the v2 xxhash update. Go 1.22 included new
compiler ability to recognize calls of Method([]byte(myString)) and not
make a copy but from looking at the call sites, I'm not sure the
compiler would recognize it as the conversion to a byte slice was
happening several calls earlier.
That's what this change set does. If we are uncomfortable with any of
these, we can do fewer of them (for example, not upgrade xxhash; and/or
not use the specialized Sum64String, etc).
For the performance issue in maz-rr, I see converting string keys to
byte slices taking between 3-5% of cpu usage on both the primary and
secondary. So while this pr doesn't address directly the increased cpu
usage on the secondary, it makes cpu usage less on both which still
feels like a win. I believe these changes are easier to review that
switching to a byte slice pool that is likely needed in other places as
the compiler provides nearly all of the correctness checks we need (we
are relying also on xxhash v2 being correct).
* helps #550
* chore: fix tests/lint
* chore: don't use assembly version; should inline
This 2 line change causes xxhash to use a purego Sum64 implementation
which allows the compiler to see that Sum64 only read the byte slice
input which them means is can skip the string to byte slice allocation
and since it can skip that, it should inline all the calls to
getPartitionStringKey and Sum64 avoiding 1 call to Sum64String which
isn't inlined.
* chore: update ci build file
the ci build doesn't use the make file!!!
* chore: revert "chore: update ci build file"
This reverts commit 94be66fde03e0bbe18004aab25c0e19051406de2.
* chore: revert "chore: don't use assembly version; should inline"
This reverts commit 67d8d06c02e17e91ba643a2991e30a49308a5283.
(cherry picked from commit 1d334c679ca025645ed93518b7832ae676499cd2)
* feat: need to update go sum
---------
Co-authored-by: Phil Bracikowski <13472206+philjb@users.noreply.github.com>
(cherry picked from commit 06ab224516)
* chore: upgrade Go to 1.19.3
This re-runs ./generate.sh and ./checkfmt.sh to format and update
source code (this is primarily responsible for the huge diff.)
* fix: update tests to reflect sorting algorithm change
* feat(query): hyper log log counting in query engine
In addition to helping with normal queries, this can improve the 'SHOW CARDINALITY'
meta-queries:
time influx -database mydb -execute 'select count_hll(sum_hll(_seriesKey)) from big'
name: big
time count_hll
---- ---------
0 200767781
influx -database mydb -execute 0.06s user 0.12s system 0% cpu 8:49.99 total
This commit adds initial empty sketches back to the tsi1 index, as well
as ensuring that ephemeral sketches in the index `LogFile` are updated
accordingly.
The commit also adds a test that verifies that the merged sketches at
the store level produce the correct results under writes, deletions and
re-opening of the store.
This commit does not provide working sketches for post-compaction on the
tsi1 index.
The new algorithm uses only one formula and needs no additional bias corrections for the entire range of cardinalities,
therefore, it is more efficient and simpler to implement. Our simulations show that the accuracy provided by the new
algorithm is as good as or better than the accuracy provided by either of HyperLogLog or HyperLogLog++. The sparse
representation was kept in to provide better low cardinality accuracy. However the linear counting and range estimations
are replaced.
WeblWabl
Brandon Pfeifer
Sam Arnold
Ben Wells
Jacob Marble
Mark Rushakoff
Edd Robinson
Seif Lotfy
Ben Johnson
Stuart Carnie