| Bug #79434 | Incorrect NUMA-specific code in buf_chunk_init() | ||
|---|---|---|---|
| Submitted: | 27 Nov 2015 9:32 | Modified: | 7 Dec 2015 17:45 |
| Reporter: | Alexey Kopytov | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: InnoDB storage engine | Severity: | S3 (Non-critical) |
| Version: | 5.7.9 | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
[1 Dec 2015 15:14]
MySQL Verification Team
Although, there is no any proof submitted, this seems to be a valid feature request. Verified.
[7 Dec 2015 17:45]
Daniel Price
Posted by developer: Fixed as of the upcoming 5.7.11, 5.8.0 release, and here's the changelog entry: In Numa-related code, the size information passed to the mbind() call in the buf_chunk_init() function was incorrect. Thank you for the bug report.
Description: I think the following code in buf_chunk_init() should use chunk->mem_pfx.m_size instead of mem_size: --- #ifdef HAVE_LIBNUMA if (srv_numa_interleave) { int st = mbind(chunk->mem, mem_size, MPOL_INTERLEAVE, numa_all_nodes_ptr->maskp, numa_all_nodes_ptr->size, MPOL_MF_MOVE); if (st != 0) { ib::warn() << "Failed to set NUMA memory policy of" " buffer pool page frames to MPOL_INTERLEAVE" " (error: " << strerror(errno) << ")."; } } #endif // HAVE_LIBNUMA --- The large memory allocator may round the requested memory block size to the OS page size, or the large page size if. As a result, some trailing pages in the chunk will not be interleaved. How to repeat: Inspect the code. Note that the code a few lines down uses chunk->mem_pfx.m_size to get the real chunk size, not mem_size