HP Tru64 UNIX and TruCluster Server Version 5.1B-5 Patch Summary and Release Notes (March 2009)

3.1.3 Support for Evaluating String Comparison Expressions as per POSIX Standards
The sh-posix built-in test is modified to evaluate string expressions as per the POSIX
standard and can interpret "(" and "!" as operands in a string comparison operation.
To produce this POSIX compliant action, set the STDS_FLAG environment variable to
ALL:
STDS_FLAG=ALL
If STDS_FLAG is not set or is set to NULL, the test function interprets "(" and "!" as
operators in string comparison and reports wrong result. This was the default action
before test was modified.
For example, consider a string comparison operation where "(" is passed as operand:
# test "(" = "abc"
The following message is displayed:
sh: test: Specify a parameter with this command.
This message indicates that the test function has failed to interpret "(" as an operand.
With the flag set, "(" and "!" will be treated as valid operands.
3.1.4 iconv Converter Support Surrogate Pairs in Unicode
The iconv converter has been modified to fix the incorrect processing of surrogate
pair characters in Unicode. In order to maintain compatibility, the new environment
variable ICONV_OLD_SURROGATE is introduced. If this environment variable is set to
a non-NULL value, iconv converter behaves in the same manner as before, that is,
iconv converter continues to produce wrong results for Unicode surrogate pairs.
3.1.5 New Sysconfig Tunable to Reduce Contention on AdvFS Frag Files
A new sysconfig tunable AdvfsFragGroupDealloc has been introduced to set the
frag group deallocation policy for the AdvFS filesystem. Using this tunable, you can
enable or disable the frag group deallocation policy. The default is enabled .
File operations such as rm and close, which release a single frag, can trigger the frag
group deallocation process when a list of free frags is encountered. This process holds
a lock while processing the frag group. Any other process or thread that tries to
manipulate the same frag group experiences a hang due to lock contention. The hang
lasts for the duration of the frag group processing. This situation arises when the frag
file of a fileset is large and too many files are present with frag. The
AdvfsFragGroupDealloc tunable helps in disabling the frag group deallocation,
which reduces the lock contention on the frag file.
The AdvfsFragGroupDealloc tunable can be added to the /etc/sysconfigtab
file, and a value can be assigned as per the desired frag group deallocation policy.
Placing the tunable in the /etc/sysconfigtab file will make the value persist across
system reboots. Alternatively, /sbin/sysconfig –r can be used to assign the value
for the tunable. However, this does not persist across system reboots.
36 Tru64 UNIX Patches