RHBA-2014:1594 - Bug Fix Advisory

Topic

Updated numad packages that fix several bugs are now available for Red Hat
Enterprise Linux 6.

Description

The numad packages provide a daemon for NUMA (Non-Uniform Memory Architecture)
systems, monitors NUMA characteristics and manages placement of processes and
memory to minimize memory latency. The packages also provide an interface that
can be used to query the numad daemon for the best manual placement of an
application.

This update fixes the following bugs:

• Previously, running the numad daemon on a system executing a process with very

large resident memory, such as a Windows Server 2012 guest, could cause memory
swapping. As a consequence, significant latencies under some circumstances
occurred on the system, which could in turn lead to other processes, such as
qemu-kvm, becoming unresponsive. With this update, numad no longer causes memory
swapping in the above scenario, and the consequent latencies and hangs no longer
occur. (BZ#872524)

• Prior to this update, when a process bound to a set of NUMA nodes depleted the

system memory, the system started memory swapping instead of using other NUMA
nodes for memory allocation. Consequently, the system experienced significant
latencies or became unresponsive. With this update, numad unbinds memory nodes
after moving the process memory, which allows for other nodes to be used for
memory allocation, and thus prevents the described latencies and hangs.
(BZ#999062)

• Previously, the numad daemon ignored existing control groups when localizing

QEMU threads, and as a consequence, it incorrectly consolidated all running
threads into a single control group. This update introduces numad support for
multiple control groups, and numad therefore no longer moves QEMU threads into
undesired control groups. (BZ#1011908)

Users of numad are advised to upgrade to these updated packages, which fix these
bugs.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386

Fixes

• BZ - 872524 - windows server 2012 guest w/ 256GB memory always be killed only when numad is enabled on host(w/ 512GB memory)

CVEs

(none)

References

(none)