Thanks for your speedy testing! I am observing comparable latencies *when the index geometry (ie number of segments)* is unchanged. Agree we can leave this for a later day. I'll proceed to cut 9.4 artifacts
On Mon, Sep 19, 2022 at 11:02 AM Mayya Sharipova <mayya.sharip...@elastic.co.invalid> wrote: > It would be great if you all are able to test again with >> https://github.com/apache/lucene/pull/11781/ applied > > > > I ran the ann benchmarks with this change, and was happy to confirm that > in my test recall with this PR is the same as in 9.3 branch, although QPS > is lower, but we can investigate QPSs later. > > glove-100-angular M:16 efConstruction:100 > 9.3 recall9.3 QPSthis PR recallthis PR QPS > n_cands=10 0.620 2745.933 0.620 1675.500 > n_cands=20 0.680 2288.665 0.680 1512.744 > n_cands=40 0.746 1770.243 0.746 1040.240 > n_cands=80 0.809 1226.738 0.809 695.236 > n_cands=120 0.843 948.908 0.843 525.914 > n_cands=200 0.878 671.781 0.878 351.529 > n_cands=400 0.918 392.265 0.918 207.854 > n_cands=600 0.937 282.403 0.937 144.311 > n_cands=800 0.949 214.620 0.949 116.875 > > On Sun, Sep 18, 2022 at 6:25 PM Michael Sokolov <msoko...@gmail.com> > wrote: > >> OK, I think I was wrong about latency having increased due to a change >> in KnnGraphTester -- I did some testing there and couldn't reproduce. >> There does seem to be a slight vector search latency increase, >> possibly noise, but maybe due to the branching introduced to check >> whether to do byte vs float operations? It would be a little >> surprising if that were the case given the small number of branchings >> compared to the number of multiplies in dot-product though. >> >> On Sun, Sep 18, 2022 at 3:25 PM Michael Sokolov <msoko...@gmail.com> >> wrote: >> > >> > Thanks for the deep-dive Julie. I was able to reproduce the changing >> > recall. I had introduced some bugs in the diversity checks (that may >> > have partially canceled each other out? it's hard to understand what >> > was happening in the buggy case) and posted a fix today >> > https://github.com/apache/lucene/pull/11781. >> > >> > There are a couple of other outstanding issues I found while doing a >> > bunch of git bisecting; >> > >> > I think we might have introduced a (test-only) performance regression >> > in KnnGraphTester >> > >> > We may still be over-allocating the size of NeighborArray, leading to >> > excessive segmentation? I wonder if we could avoid dynamic >> > re-allocation there, and simply initialize every neighbor array to >> > 2*M+1. >> > >> > While I don't think these are necessarily blockers, given that we are >> > releasing HNSW improvements, it seems like we should address these, >> > especially as the build-graph-on-index is one of the things we are >> > releasing, and it is (may be?) impacted. I will see if I can put up a >> > patch or two. >> > >> > It would be great if you all are able to test again with >> > https://github.com/apache/lucene/pull/11781/ applied >> > >> > -Mike >> > >> > On Fri, Sep 16, 2022 at 11:07 AM Adrien Grand <jpou...@gmail.com> >> wrote: >> > > >> > > Thank you Mike, I just backported the change. >> > > >> > > On Thu, Sep 15, 2022 at 6:32 PM Michael Sokolov <msoko...@gmail.com> >> wrote: >> > >> >> > >> it looks like a small bug fix, we have had on main (and 9.x?) for a >> > >> while now and no test failures showed up, I guess. Should be OK to >> > >> port. I plan to cut artifacts this weekend, or Monday at the latest, >> > >> but if you can do the backport today or tomorrow, that's fine by me. >> > >> >> > >> On Thu, Sep 15, 2022 at 10:55 AM Adrien Grand <jpou...@gmail.com> >> wrote: >> > >> > >> > >> > Mike, I'm tempted to backport >> https://github.com/apache/lucene/pull/1068 to branch_9_4, which is a >> bugfix that looks pretty safe to me. What do you think? >> > >> > >> > >> > On Tue, Sep 13, 2022 at 4:11 PM Mayya Sharipova < >> mayya.sharip...@elastic.co.invalid> wrote: >> > >> >> >> > >> >> Thanks for running more tests, Michael. >> > >> >> It is encouraging that you saw a similar performance between 9.3 >> and 9.4. I will also run more tests with different parameters. >> > >> >> >> > >> >> On Tue, Sep 13, 2022 at 9:30 AM Michael Sokolov < >> msoko...@gmail.com> wrote: >> > >> >>> >> > >> >>> As a follow-up, I ran a test using the same parameters as above, >> only >> > >> >>> changing M=200 to M=16. This did result in a single segment in >> both >> > >> >>> cases (9.3, 9.4) and the performance was pretty similar; within >> noise >> > >> >>> I think. The main difference I saw was that the 9.3 index was >> written >> > >> >>> using CFS: >> > >> >>> >> > >> >>> 9.4: >> > >> >>> recall latency nDoc fanout maxConn beamWidth visited >> index ms >> > >> >>> 0.755 1.36 1000000 100 16 100 200 891402 >> 1.00 >> > >> >>> post-filter >> > >> >>> -rw-r--r-- 1 sokolovm amazon 382M Sep 13 13:06 >> > >> >>> _0_Lucene94HnswVectorsFormat_0.vec >> > >> >>> -rw-r--r-- 1 sokolovm amazon 262K Sep 13 13:06 >> > >> >>> _0_Lucene94HnswVectorsFormat_0.vem >> > >> >>> -rw-r--r-- 1 sokolovm amazon 131M Sep 13 13:06 >> > >> >>> _0_Lucene94HnswVectorsFormat_0.vex >> > >> >>> >> > >> >>> 9.3: >> > >> >>> recall latency nDoc fanout maxConn beamWidth visited >> index ms >> > >> >>> 0.775 1.34 1000000 100 16 100 4033 977043 >> > >> >>> rw-r--r-- 1 sokolovm amazon 297 Sep 13 13:26 _0.cfe >> > >> >>> -rw-r--r-- 1 sokolovm amazon 516M Sep 13 13:26 _0.cfs >> > >> >>> -rw-r--r-- 1 sokolovm amazon 340 Sep 13 13:26 _0.si >> > >> >>> >> > >> >>> On Tue, Sep 13, 2022 at 8:50 AM Michael Sokolov < >> msoko...@gmail.com> wrote: >> > >> >>> > >> > >> >>> > I ran another test. I thought I had increased the RAM buffer >> size to >> > >> >>> > 8G and heap to 16G. However I still see two segments in the >> index that >> > >> >>> > was created. And looking at the infostream I see: >> > >> >>> > >> > >> >>> > dir=MMapDirectory@ >> /local/home/sokolovm/workspace/knn-perf/glove-100-angular.hdf5-train-200-200.index >> > >> >>> > lockFactory=org\ >> > >> >>> > .apache.lucene.store.NativeFSLockFactory@4466af20 >> > >> >>> > index= >> > >> >>> > version=9.4.0 >> > >> >>> > analyzer=org.apache.lucene.analysis.standard.StandardAnalyzer >> > >> >>> > ramBufferSizeMB=8000.0 >> > >> >>> > maxBufferedDocs=-1 >> > >> >>> > ... >> > >> >>> > perThreadHardLimitMB=1945 >> > >> >>> > ... >> > >> >>> > DWPT 0 [2022-09-13T02:42:53.329404950Z; main]: flush postings >> as >> > >> >>> > segment _6 numDocs=555373 >> > >> >>> > IW 0 [2022-09-13T02:42:53.330671171Z; main]: 0 msec to write >> norms >> > >> >>> > IW 0 [2022-09-13T02:42:53.331113184Z; main]: 0 msec to write >> docValues >> > >> >>> > IW 0 [2022-09-13T02:42:53.331320146Z; main]: 0 msec to write >> points >> > >> >>> > IW 0 [2022-09-13T02:42:56.424195657Z; main]: 3092 msec to >> write vectors >> > >> >>> > IW 0 [2022-09-13T02:42:56.429239944Z; main]: 4 msec to finish >> stored fields >> > >> >>> > IW 0 [2022-09-13T02:42:56.429593512Z; main]: 0 msec to write >> postings >> > >> >>> > and finish vectors >> > >> >>> > IW 0 [2022-09-13T02:42:56.430309031Z; main]: 0 msec to write >> fieldInfos >> > >> >>> > DWPT 0 [2022-09-13T02:42:56.431721622Z; main]: new segment has >> 0 deleted docs >> > >> >>> > DWPT 0 [2022-09-13T02:42:56.431921144Z; main]: new segment has >> 0 >> > >> >>> > soft-deleted docs >> > >> >>> > DWPT 0 [2022-09-13T02:42:56.435738086Z; main]: new segment has >> no >> > >> >>> > vectors; no norms; no docValues; no prox; freqs >> > >> >>> > DWPT 0 [2022-09-13T02:42:56.435952356Z; main]: >> > >> >>> > flushedFiles=[_6_Lucene94HnswVectorsFormat_0.vec, _6.fdm, >> _6.fdt, _6_\ >> > >> >>> > Lucene94HnswVectorsFormat_0.vem, _6.fnm, _6.fdx, >> > >> >>> > _6_Lucene94HnswVectorsFormat_0.vex] >> > >> >>> > DWPT 0 [2022-09-13T02:42:56.436121861Z; main]: flushed >> codec=Lucene94 >> > >> >>> > DWPT 0 [2022-09-13T02:42:56.437691468Z; main]: flushed: >> segment=_6 >> > >> >>> > ramUsed=1,945.002 MB newFlushedSize=1,065.701 MB \ >> > >> >>> > docs/MB=521.134 >> > >> >>> > >> > >> >>> > so I think it's this perThreadHardLimit that is triggering the >> > >> >>> > flushes? TBH this isn't something I had seen before; but the >> docs say: >> > >> >>> > >> > >> >>> > /** >> > >> >>> > * Expert: Sets the maximum memory consumption per thread >> triggering >> > >> >>> > a forced flush if exceeded. A >> > >> >>> > * {@link DocumentsWriterPerThread} is forcefully flushed >> once it >> > >> >>> > exceeds this limit even if the >> > >> >>> > * {@link #getRAMBufferSizeMB()} has not been exceeded. This >> is a >> > >> >>> > safety limit to prevent a {@link >> > >> >>> > * DocumentsWriterPerThread} from address space exhaustion >> due to >> > >> >>> > its internal 32 bit signed >> > >> >>> > * integer based memory addressing. The given value must be >> less >> > >> >>> > that 2GB (2048MB) >> > >> >>> > * >> > >> >>> > * @see #DEFAULT_RAM_PER_THREAD_HARD_LIMIT_MB >> > >> >>> > */ >> > >> >>> > >> > >> >>> > On Mon, Sep 12, 2022 at 6:28 PM Michael Sokolov < >> msoko...@gmail.com> wrote: >> > >> >>> > > >> > >> >>> > > Hi Mayya, thanks for persisting - I think we need to wrestle >> this to >> > >> >>> > > the ground for sure. In the test I ran, RAM buffer was the >> default >> > >> >>> > > checked in, which is weirdly: 1994MB. I did not specifically >> set heap >> > >> >>> > > size. I used maxConn/M=200. I'll try with larger buffer to >> see if I >> > >> >>> > > can get 9.4 to produce a single segment for the same test >> settings. I >> > >> >>> > > see you used a much smaller M (16), which should have >> produced quite >> > >> >>> > > small graphs, and I agree, should have been a single >> segment. Were you >> > >> >>> > > able to verify the number of segments? >> > >> >>> > > >> > >> >>> > > Agree that decrease in recall is not expected when more >> segments are produced. >> > >> >>> > > >> > >> >>> > > On Mon, Sep 12, 2022 at 1:51 PM Mayya Sharipova >> > >> >>> > > <mayya.sharip...@elastic.co.invalid> wrote: >> > >> >>> > > > >> > >> >>> > > > Hello Michael, >> > >> >>> > > > Thanks for checking. >> > >> >>> > > > Sorry for bringing this up again. >> > >> >>> > > > First of all, I am ok with proceeding with the Lucene 9.4 >> release and leaving the performance investigations for later. >> > >> >>> > > > >> > >> >>> > > > I am interested in what's the maxConn/M value you used for >> your tests? What was the heap memory and the size of the RAM buffer for >> indexing? >> > >> >>> > > > Usually, when we have multiple segments, recall should >> increase, not decrease. But I agree that with multiple segments we can see >> a big drop in QPS. >> > >> >>> > > > >> > >> >>> > > > Here is my investigation with detailed output of the >> performance difference between 9.3 and 9.4 releases. In my tests I used a >> large indexing buffer (2Gb) and large heap (5Gb) to end up with a single >> segment for both 9.3 and 9.4 tests, but still see a big drop in QPS in 9.4. >> > >> >>> > > > >> > >> >>> > > > Thank you. >> > >> >>> > > > >> > >> >>> > > > >> > >> >>> > > > >> > >> >>> > > > >> > >> >>> > > > >> > >> >>> > > > On Fri, Sep 9, 2022 at 12:21 PM Alan Woodward < >> romseyg...@gmail.com> wrote: >> > >> >>> > > >> >> > >> >>> > > >> Done. Thanks! >> > >> >>> > > >> >> > >> >>> > > >> > On 9 Sep 2022, at 16:32, Michael Sokolov < >> msoko...@gmail.com> wrote: >> > >> >>> > > >> > >> > >> >>> > > >> > Hi Alan - I checked out the interval queries patch; >> seems pretty safe, >> > >> >>> > > >> > please go ahead and port to 9.4. Thanks! >> > >> >>> > > >> > >> > >> >>> > > >> > Mike >> > >> >>> > > >> > >> > >> >>> > > >> > On Fri, Sep 9, 2022 at 10:41 AM Alan Woodward < >> romseyg...@gmail.com> wrote: >> > >> >>> > > >> >> >> > >> >>> > > >> >> Hi Mike, >> > >> >>> > > >> >> >> > >> >>> > > >> >> I’ve opened >> https://github.com/apache/lucene/pull/11760 as a small bug fix PR for a >> problem with interval queries. Am I OK to port this to the 9.4 branch? >> > >> >>> > > >> >> >> > >> >>> > > >> >> Thanks, Alan >> > >> >>> > > >> >> >> > >> >>> > > >> >> On 2 Sep 2022, at 20:42, Michael Sokolov < >> msoko...@gmail.com> wrote: >> > >> >>> > > >> >> >> > >> >>> > > >> >> NOTICE: >> > >> >>> > > >> >> >> > >> >>> > > >> >> Branch branch_9_4 has been cut and versions updated to >> 9.5 on stable branch. >> > >> >>> > > >> >> >> > >> >>> > > >> >> Please observe the normal rules: >> > >> >>> > > >> >> >> > >> >>> > > >> >> * No new features may be committed to the branch. >> > >> >>> > > >> >> * Documentation patches, build patches and serious bug >> fixes may be >> > >> >>> > > >> >> committed to the branch. However, you should submit >> all patches you >> > >> >>> > > >> >> want to commit to Jira first to give others the chance >> to review >> > >> >>> > > >> >> and possibly vote against the patch. Keep in mind that >> it is our >> > >> >>> > > >> >> main intention to keep the branch as stable as >> possible. >> > >> >>> > > >> >> * All patches that are intended for the branch should >> first be committed >> > >> >>> > > >> >> to the unstable branch, merged into the stable branch, >> and then into >> > >> >>> > > >> >> the current release branch. >> > >> >>> > > >> >> * Normal unstable and stable branch development may >> continue as usual. >> > >> >>> > > >> >> However, if you plan to commit a big change to the >> unstable branch >> > >> >>> > > >> >> while the branch feature freeze is in effect, think >> twice: can't the >> > >> >>> > > >> >> addition wait a couple more days? Merges of bug fixes >> into the branch >> > >> >>> > > >> >> may become more difficult. >> > >> >>> > > >> >> * Only Jira issues with Fix version 9.4 and priority >> "Blocker" will delay >> > >> >>> > > >> >> a release candidate build. >> > >> >>> > > >> >> >> > >> >>> > > >> >> >> --------------------------------------------------------------------- >> > >> >>> > > >> >> To unsubscribe, e-mail: >> dev-unsubscr...@lucene.apache.org >> > >> >>> > > >> >> For additional commands, e-mail: >> dev-h...@lucene.apache.org >> > >> >>> > > >> >> >> > >> >>> > > >> >> >> > >> >>> > > >> > >> > >> >>> > > >> > >> --------------------------------------------------------------------- >> > >> >>> > > >> > To unsubscribe, e-mail: >> dev-unsubscr...@lucene.apache.org >> > >> >>> > > >> > For additional commands, e-mail: >> dev-h...@lucene.apache.org >> > >> >>> > > >> > >> > >> >>> > > >> >> > >> >>> > > >> >> > >> >>> > > >> >> --------------------------------------------------------------------- >> > >> >>> > > >> To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org >> > >> >>> > > >> For additional commands, e-mail: >> dev-h...@lucene.apache.org >> > >> >>> > > >> >> > >> >>> >> > >> >>> >> --------------------------------------------------------------------- >> > >> >>> To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org >> > >> >>> For additional commands, e-mail: dev-h...@lucene.apache.org >> > >> >>> >> > >> > >> > >> > >> > >> > -- >> > >> > Adrien >> > >> >> > >> --------------------------------------------------------------------- >> > >> To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org >> > >> For additional commands, e-mail: dev-h...@lucene.apache.org >> > >> >> > > >> > > >> > > -- >> > > Adrien >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org >> For additional commands, e-mail: dev-h...@lucene.apache.org >> >>
