Segmentation fault while building index on NGT-QG

[abhishekukmeesho]

Hi, I was trying to build a NGT-QG index on top of an ANNG index. The qbg create-qg <<index_path>> works fine. But when I run the qbg build-qg <<index_path>>, it leads to segmentation fault. I tried to capture the backtrace via GDB and this was the output:

root@mac1:/mnt/disks/disk3/index# gdb /usr/local/bin/qbg
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Reading symbols from /usr/local/bin/qbg...
(No debugging symbols found in /usr/local/bin/qbg)

(gdb) run build_qg <<index_path>>
.
.
.
Thread 1 "qbg" received signal SIGSEGV, Segmentation fault.
0x00007ffff7d44a41 in NGTQG::QuantizedGraphRepository::construct(NGT::GraphRepository&, NGTQ::Index&, unsigned long) () from /usr/local/lib/libngt.so.2

Any help is appreciated, TIA.

[masajiro]

If you provide me with the ANNG index, I'll take a look at it for you.

[abhishekukmeesho]

If you provide me with the ANNG index, I'll take a look at it for you.

My ANNG index is quite large ( ~70G). So I'm not sure how to share it.

[masajiro]

Can't you generate a small index that can reproduce the segmentation fault?