Oracle Linux Release Notes
The following packages were added upstream for this release (5.5) which were not in the previous update release (5.4)
Oracle Linux 5.5 ships with following three sets of kernel packages
This section covers significant changes in the default kernel in this release.
This kernel includes bug fixes added by Oracle on top of unmodified kernel.
Fix qla not to query hccr [orabug 8746702]
update rds to 4.0-ora-1.4.2-10 [orabug 9168046]
Revert return code check to avoid EIO [orabug 9448515]
Check to see if hypervisor supports memory reservation change [orabug 7556514]
Add entropy support to igb [orabug 7607479]
Convert ENETUNREACH to ENOTCONN [orabug 7689332]
Add xen pv/bonding netconsole support [orabug 6993043]
Shrink zone patch [orabug 6086839]
Fix aacraid not to reset during kexec [orabug 8516042]
Fix failure of file creation from hpux client [orabug 7579314]
FP register state is corrupted during the handling a SIGSEGV [orabug 7708133]
This kernel needs to be manually installed. Use following steps to install this kernel
The Unbreakable Enterprise Kernel is based on the upstream kernel 2.6.32-21 stable source tree with additional performance improvements, including:
The Unbreakable Enterprise Kernel is available for the x86_64 architecture.
The Unbreakable Enterprise Kernel is tickless. In the tickless kernel, timer interrupts are performed on demand rather than at a predetermined frequency. This allows CPUs to stay in a low power state when the system is idle, reducing overall power consumption
OFED implements Remote Direct Memory Access (RDMA) and kernel bypass mechanisms to deliver high-efficiency computing, wire-speed messaging, ultra-low microsecond latencies and fast I/O for servers, block storage and file systems.
The Unbreakable Enterprise Kernel includes OCFS2 1.6 kernel module. Following are the new features included:
The performance counter subsystem keeps track of hardware and software events without affecting performance and enables you to do tracing and performance analysis. includes the a tool called perf for analysis.
Latency can be defined as follows: an applications wants to run and execute code, but is blocked by the kernel because some required resource is not available. LatencyTOP is a Linux tool for software developers (both kernel and userspace), aimed at identifying where system latency occurs, and what kind of operation or action is causing the latency to happen. By identifying this, developers can then change the code to avoid the worst latency hiccups.
The kernel block layer will detect devices that claim to be fast, solid state storage and tune itself accordingly. The result of this detection can be found in:
Where xxx is the block device. Echoing a 0 or a 1 into this file will force the value to off or on. When assuming a device is an SSD, the block layer will try harder to immediately dispatch the IO to the device.
IO affinity ensures processing of a completed IO is handled by the same CPU that initiated the IO. It can have a fairly large impact on performance, especially on large NUMA machines.
IO affinity is turned on by default, but it can be controlled via the tunable in /sys/block/xxx/queue/rq_affinity
example: echo 1> /sys/block/sda/queue/rq_affinity will turn it on.
RPS distributes the load of received packet processing across multiple CPUs. This solution allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. This removes a bottleneck when a single core is saturated processing network interrupts.
fallocate() is a new system call which will allow applications to preallocate space to any file(s) in a file system. Applications can get a guarantee of space for particular file(s) - even if later the system becomes full. Using this method of allocation can dramatically speed up the creation of large files such as those used for virtual machine images.
The Unbreakable Enterprise Kernel and other packages are available on the Unbreakable Linux Network (ULN). Login to the Unbreakable Linux Network(ULN) and subscribe to the Oracle Linux 5 Latest channel to get updates to the Unbreakable Enterprise Kernel. The initial set of packages are also available on public-yum.oracle.com.
1. Install the Unbreakable Enterprise Kernel and dependent packages (required):
# up2date kernel
2. Optional but recommended.
Install additonal packages needed for Oracle Database Installation:
# up2date oracle-validated
Install additional recommended packages (superset of packages installed by oracle-validated):
# up2date oracle-linux
Note: If the ofa kernel module is needed, install this module using the following steps:
Upgrade to the Unbreakable Enterprise Kernel using one of the methods above
Reboot your system and check that you are booting the Unbreakable Enterprise Kernel (uname –r should say 2.6.32-100.0.19.el5)
# update ofa-`uname -r`
List of packages included
On some hardware, the console may appear to hang during the boot process after starting udev. But the system does boot up properly and is accessible. A workaround to this problem is to add ‘nomodeset’ as a kernel boot parameter in /etc/grub.conf:
kernel /vmlinuz-2.6.32-100.0.10.el5.x86_64 ro root=/dev/sd0 nomodeset
Currently, this configuration does not boot properly. Please do not install this kernel in a hardware virtualized guest that uses paravirtualized drivers (PVHVM). Installing the kernel in a hardware virtualized guest without paravirtualized drivers (HVM) or in a paravirtualized guest (PV) works without problems.
The following error may be encountered while mounting an NFS filesystem:
"SVC: FAILED TO REGISTER LOCKDV1 RPC SERVICE (ERRNO 97)."
This is an informative message and can be ignored
Please use the following steps to configure the serial console in a paravirtualized guest (PV) using the Unbreakable Enterprise kernel (updates are in the guest):.
1.change the kernel boot parameter 'console=xvc0' to 'console=hvc0' in the /etc/grub.conf:
kernel /vmlinuz-2.6.32-100.0.19.el5 ro root=/dev/sd0 console=tty0 console=hvc0
2. add an 'hvc0' entry to /etc/inittab:
co:2345:respawn:/sbin/agetty hvc0 9600 vt100-nav
3. add an 'hvc0' entry to /etc/securetty
On some hardware startup of X environment may fail after upgrading to Unbreakable Enterprise Kernel with following Error:
Fatal server error:
Cannot run in framebuffer mode. Please specify busIDs for all
To workaround this issue reconfigure X using command "X -configure" and use generated configuration file to start X environment.
With unbreakable Enterprise Kernel higher memory setting is required for crashkernel option in /etc/grub.conf file. Booting with crashkernel=128M@16M will result in following error:
crashkernel reservation failed - memory is in use
Minimum value for crashkernel option is 128M@32M. Based on the system configuration higher value may be required. If kdump service loading fails increase the second value (32M). If system hangs or crashes with out of memory during dumping core increase the first value (128M)
The path checker fails to recognise the restored storage path, thus fail to restore the device-mapper multipaths and shows status as faulty. Need to restart mutlipathd for path checker to recognise restored storage paths.
This error at boot can be safely ignored. If this error is encountered at runtime (while attempting to set the hardware clock) please install the provided util-linux RPM.
Unbreakable Enterprise kernel does not recognise /dev/hd* entries in hardware virtualized guests. Make sure to use sables for all /dev/hd* devices in /etc/fstab before updating the kernel. This kernel package will not install if / or /boot partition is using devices like /dev/hd* in /etc/fstab.
The following Technology Preview features are currently not supported under Oracle Linux 5 and may not be functionally complete.
Brocade BFA Fibre-Channel/FCoE driver
TrouSerS and tpm-tools
SGPIO Support for dmraid
Kernel Tracepoint Facility
Device Failure Monitoring of RAID sets
Software based Fibre Channel over Ethernet (FCoE)
cman fence_virsh fence agent
glibc new MALLOC behaviour
These features are not suitable for
production use. However, these features are included to provide the
feature with wider exposure.
2. Following packages can not co-exists due to file conflict
3. If updating from Oracle Linux 5 GA or RHEL 5 GA using up2date, you may encounter the following error:
Unresolvable chain of dependencies:
xen-3.0.3-64.el5 requires xen-hypervisor-abi = 3.1
This happens because a kernel-xen package update
is needed by the xen package, but 'kernel*' is part of the up2date
pkgSkipList. To get around this, add 'xen;xen-devel;' to the the
pkgSkipList line in /etc/sysconfig/rhn/up2date and then run up2date. You
can update the xen and kernel-xen packages together later via 'up2date --force
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY