The Virtualization Cookbook for SLES 10 SP2 - z/VM - IBM

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/sys/devices/system/cpu/cpu9
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After a few more minutes, all of the CPUs should be activated.
► Kill the processes with the killall command, then verify that the loops have stopped:
# killall cat
bash: line 1: 2450 Terminated cat /dev/zero > /dev/null
bash: line 1: 2452 Terminated cat /dev/zero > /dev/null
bash: line 1: 2451 Terminated cat /dev/zero > /dev/null
bash: line 1: 2457 Terminated cat /dev/zero > /dev/null
bash: line 1: 2456 Terminated cat /dev/zero > /dev/null
[1] Exit 143 bash -c "cat /dev/zero > /dev/null"
[2] Exit 143 bash -c "cat /dev/zero > /dev/null"
...
# pstree -G | grep cat
No output shows that the processes to create a workload have been stopped.
13.7.3 Setting memory sizes with cpuplugd
Memory sizes can also be set by the cpuplugd service. However, unlike CPUs, there is no
good generic default value. The following example is in the Device Drivers book:
MEMPLUG = "swaprate > freemem+10 & freemem+10 < apcr"
MEMUNPLUG = "swaprate > freemem + 10000"
However, this is just a starting point to explain the syntactical structure of a rule. Do not use
this configuration in production. You should test any setting that you want to implement
against a representative workload that your Linux systems will be running. Details are beyond
the scope of this section.
13.8 Hardware cryptographic support for OpenSSH
This section shows how to copy a test file with OpenSSH, first without any crypto
acceleration. Then crypto acceleration for OpenSSH is enabled and the same file is copied
again. A much higher throughput rate should be observed. The prerequisite for using
hardware cryptography is to have a firmware level of LIC 3863 installed on your System z
CEC. (TODO: how to query this?)
This section is based on the white paper First experiences with hardware cryptographic
support for OpenSSH with Linux for System z, by Manfred Gnirss, Winfried Münch, Klaus
Werner and Arthur Winterling. It is on the Web at:
http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/WP101690
This section only shows a single example of crypto acceleration. For a much more complete
and detailed analysis, see the white paper.
To test copying a file with and without cryptographic acceleration, perform the following steps:
► Start an SSH session to a Linux.
► Create a 200 MB test file for copying in the /tmp/ directory:
# cd /tmp
# dd if=/dev/zero of=testdata.txt bs=1048576 count=200
200+0 records in
Chapter 13. Miscellaneous recipes 213