Oh, thanks for reporting and tracking this down! On Fri, Apr 24, 2026, 4:50 AM Rahul Goswami <[email protected]> wrote:
> Found the bug. It was an issue due to the CUDA runtime library not being > available before the first call to cuVS's CuVSServiceProvider. There is an > initialization race between two code paths and the wrong one wins. When > this happens, the GPU resource *seems unavailable* to the indexing code > path and it falls back to using CPU based Lucene99HnswVectorsWriter > instead. > > > Submitted a PR : https://github.com/apache/solr/pull/4328 > > -Rahul > > On Wed, Apr 22, 2026 at 2:16 AM Rahul Goswami <[email protected]> > wrote: > > > Hi, > > I was trying the GPU accelerated vector indexing in Solr 10.0 on an > Nvidia > > L40S GPU following the steps documented here: > > > https://solr.apache.org/guide/solr/latest/query-guide/dense-vector-search.html#gpu-acceleration > > > > I am running Solr in standalone mode and made the schema and solrconfig > > changes to the techproducts core. I indexed 100 mock vectors and the > > /update call succeeds. However, when I look closely at the logs, I notice > > that it silently falls back to CPU based indexing. > > > > I think I have all the prerequisites that the documentation mentions. > > Trying to debug this with Claude I burnt through 2 session limits while > it > > kept gaslighting me with being "almost there" for over 4 hours without > any > > luck. > > > > Help would be much appreciated! > > > > *Environment details:* > > $ *nvcc --version* > > nvcc: NVIDIA (R) Cuda compiler driver > > Copyright (c) 2005-2026 NVIDIA Corporation > > Built on Thu_Mar_19_11:12:51_PM_PDT_2026 > > Cuda compilation tools, *release 13.2, V13.2.78* > > Build cuda_13.2.r13.2/compiler.37668154_0 > > > > $*echo $LD_LIBRARY_PATH* (libcuvs is part of LD_LIBRARY_PATH and I > > verified that libcuvs_c.so is present) > > /home/ubuntu/Work/solr/libcuvs-env/lib/python3.10/site-packages/ > > *libcuvs/lib64* > > > :/home/ubuntu/Work/solr/libcuvs-env/lib/python3.10/site-packages/librmm/lib64:/home/ubuntu/Work/solr/libcuvs-env/lib/python3.10/site-packages/rapids_logger/lib64:/usr/local/cuda-13/lib64:/usr/local/cuda-12.9/lib:/usr/local/cuda-12.9/lib64:/usr/local/cuda-12.9:/usr/local/cuda-12.9/targets/x86_64-linux/lib/:/usr/local/cuda-12.9/extras/CUPTI/lib64:/opt/amazon/openmpi/lib:/usr/local/lib:/usr/lib > > > > $ *java -version* > > openjdk version "22.0.2" 2024-07-16 > > OpenJDK Runtime Environment Temurin-22.0.2+9 (build 22.0.2+9) > > OpenJDK 64-Bit Server VM Temurin-22.0.2+9 (build 22.0.2+9, mixed mode, > > sharing) > > > > *solr.log:* > > 2026-04-22 05:45:26.122 INFO (qtp858232531-60-null-3) [ x:techproducts > > t:null-3] o.a.s.c.CuVSCodec Initializing > > Lucene99AcceleratedHNSWVectorsFormat with parameter values: > > cuvsWriterThreads 32, cuvsIntGraphDegree 128, cuvsGraphDegree 64, > > cuvsHnswLayers 1, cuvsHnswM 16, cuvsHnswEfConstruction 100 > > 2026-04-22 05:45:26.122 INFO (qtp858232531-60-null-3) [ x:techproducts > > t:null-3] o.a.s.c.CuVSCodec Initializing > > Lucene99AcceleratedHNSWVectorsFormat with parameter values: > > cuvsWriterThreads 32, cuvsIntGraphDegree 128, cuvsGraphDegree 64, > > cuvsHnswLayers 1, cuvsHnswM 16, cuvsHnswEfConstruction 100 > > 2026-04-22 05:45:26.122 WARN (qtp858232531-60-null-3) [ x:techproducts > > t:null-3] c.n.c.l.Lucene99AcceleratedHNSWVectorsFormat *GPU based > > indexing not supported, falling back to using the > Lucene99HnswVectorsWriter* > > 2026-04-22 05:45:26.391 INFO (qtp858232531-60-null-3) [ x:techproducts > > t:null-3] o.a.s.u.p.LogUpdateProcessorFactory path=/update > > params={commit=true}{add=[mock_product_0001 (1863148346926956544), > > mock_product_0002 (1863148346933248000), mock_product_0003 > > (1863148346934296576), mock_product_0004 (1863148346936393728), > > mock_product_0005 (1863148346937442304), mock_product_0006 > > (1863148346939539456), mock_product_0007 (1863148346940588032), > > mock_product_0008 (1863148346946879488), mock_product_0009 > > (1863148346947928064), mock_product_0010 (1863148346950025216), ... (100 > > adds)], commit=} 0 272 > > > > Thanks, > > Rahul > > >
