Red Hat ENTERPRISE 5.4 RELEASE NOTES, Manual

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kernel
299
Stopping tasks:
======================================================================
stopping tasks timed out after 20 seconds (1 tasks remaining):
cciss_scan00
Restarting tasks...<6> Strange, cciss_scan00 not stopped
done
(BZ#513472)
48
• The kernel is unable to properly detect whether there is media present in a CD-ROM drive during
kickstart installs. The function to check the presence of media incorrectly interprets the "logical unit
is becoming ready" sense, returning that the drive is ready when it is not. To work around this issue,
wait several seconds between inserting a CD and asking the installer (anaconda) to refresh the CD.
(BZ#510632)
49
• When a cciss device is under high I/O load, the kdump kernel may panic and the vmcore dump may
not be saved successfully.
(BZ#509790)
50
• Applications attempting to
malloc
memory approximately larger than the size of the physical
memory on the node on a NUMA system may hang or appear to stall. This issue may occur on a
NUMA system where the remote memory distance, as defined in SLIT, is greater than 20 and RAM
based filesystem like
tmpfs
or
ramfs
is mounted.
To work around this issue, unmount all RAM based filesystems (i.e. tmpfs or ramfs). If unmounting
the RAM based filesystems is not possible, modify the application to allocate lesser memory. Finally,
if modifying the application is not possible, disable NUMA memory reclaim by running:
sysctl vm.zone_reclaim_mode=0
Important
Turning NUMA reclaim negatively effects the overall throughput of the system.
(BZ#507360)
51
• Configuring IRQ SMP affinity has no effect on some devices that use message signalled interrupts
(MSI) with no MSI per-vector masking capability. Examples of such devices include
Broadcom
NetXtreme
Ethernet devices that use the
bnx2
driver.
If you need to configure IRQ affinity for such a device, disable MSI by creating a file in
/etc/
modprobe.d/
containing the following line:
options bnx2 disable_msi=1
Alternatively, you can disable MSI completely using the kernel boot parameter
pci=nomsi
.
(BZ#432451)
52
• The
smartctl
tool cannot properly read SMART parameters from SATA devices.
(BZ#429606)
53
•
IBM T60
laptops will power off completely when suspended and plugged into a docking station. To
avoid this, boot the system with the argument
acpi_sleep=s3_bios
.
(BZ#439006)
54