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Who When What Removed Added
Red Hat Bugzilla 2021-01-07 14:06:35 UTC Pool ID sst_platform_tools_rhel_8
Red Hat One Jira (issues.redhat.com) 2021-01-07 14:10:05 UTC Link ID Red Hat Issue Tracker - Private RHELPLAN-63269
Florian Weimer 2021-01-07 14:16:13 UTC Doc Text Cause: On x86-64, the glibc implementation of string functions overestimated the amount of last-level cache available to a thread.

Consequence: Calling memcpy on large buffers would negatively impact overall cache performance of the system.

Fix: The last-level cache size is no longer scaled with the number of potential hardware threads in the system.

Result: The string functions bypass caches for large buffers, avoiding undue cache impact on the rest of the system.
Doc Type If docs needed, set a value Bug Fix
Type --- Bug
Florian Weimer 2021-01-07 15:33:05 UTC Status NEW ASSIGNED
Florian Weimer 2021-01-07 17:03:23 UTC Status ASSIGNED MODIFIED
Fixed In Version glibc-2.28-127.el8_3.2
Florian Weimer 2021-01-07 17:12:44 UTC Doc Text Cause: On x86-64, the glibc implementation of string functions overestimated the amount of last-level cache available to a thread.

Consequence: Calling memcpy on large buffers would negatively impact overall cache performance of the system.

Fix: The last-level cache size is no longer scaled with the number of potential hardware threads in the system.

Result: The string functions bypass caches for large buffers, avoiding undue cache impact on the rest of the system.
Cause: On x86-64, the glibc implementation of string functions wrongly estimated the amount of last-level cache available to a thread.

Consequence: Calling memcpy on large buffers could negatively impact overall cache performance of the system, or the memcpy call itself could be slow.

Fix: The last-level cache size is no longer scaled with the number of reported hardware threads in the system.

Result: The string functions bypass caches for large buffers (and only for large buffer), avoiding undue cache impact on the rest of the system.
errata-xmlrpc 2021-01-11 18:19:51 UTC Status MODIFIED ON_QA
Florian Weimer 2021-01-13 12:49:29 UTC Blocks 1913656
CC yoguma
Jay Shin 2021-01-14 01:33:26 UTC CC jaeshin
Link ID Red Hat Knowledge Base (Solution) 5514711
Yanhui Ma 2021-01-14 02:45:55 UTC CC yama
Sergey Kolosov 2021-02-05 19:30:43 UTC Status ON_QA VERIFIED
CC skolosov
errata-xmlrpc 2021-02-16 00:06:00 UTC Status VERIFIED RELEASE_PENDING
errata-xmlrpc 2021-02-16 14:36:33 UTC Status RELEASE_PENDING CLOSED
Resolution --- ERRATA
Last Closed 2021-02-16 14:36:33 UTC
Pavel Najman 2021-09-17 12:24:26 UTC Pool ID sst_platform_tools_rhel_8 sst_pt_pcp_rhel_8
Pavel Najman 2021-09-17 12:34:06 UTC Pool ID sst_pt_pcp_rhel_8 sst_pt_gcc_glibc_rhel_8
Mark O'Brien 2023-07-18 14:30:35 UTC Pool ID sst_pt_glibc_rhel_8 sst_pt_libraries_rhel_8

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