01-11-2012
Slow NFS when cio/dio enabled
Hi,
I have a bit of a NFS problem on AiX 6.1 : When I set the mount to cio and dio - needed for a database app - Everything slows down. The following is copying 700mb, top one is a normal mount bottom one is a mount with the cio/dio option enabled :
# ./a.sh
Wed Jan 11 11:41:24 GMT 2012
Wed Jan 11 11:41:36 GMT 2012
# ./a.sh
Wed Jan 11 11:42:09 GMT 2012
Wed Jan 11 11:44:00 GMT 2012
Has anyone any ideas of how I could sort this?
Regards
Adam
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LEARN ABOUT CENTOS
function::ctime
FUNCTION::CTIME(3stap) Time utility functions FUNCTION::CTIME(3stap)
NAME
function::ctime - Convert seconds since epoch into human readable date/time string
SYNOPSIS
ctime:string(epochsecs:long)
ARGUMENTS
epochsecs
Number of seconds since epoch (as returned by gettimeofday_s)
DESCRIPTION
Takes an argument of seconds since the epoch as returned by gettimeofday_s. Returns a string of the form
"Wed Jun 30 21:49:08 1993"
The string will always be exactly 24 characters. If the time would be unreasonable far in the past (before what can be represented with a
32 bit offset in seconds from the epoch) an error will occur (which can be avoided with try/catch). If the time would be unreasonable far
in the future, an error will also occur.
Note that the epoch (zero) corresponds to
"Thu Jan 1 00:00:00 1970"
The earliest full date given by ctime, corresponding to epochsecs -2147483648 is "Fri Dec 13 20:45:52 1901". The latest full date given by
ctime, corresponding to epochsecs 2147483647 is "Tue Jan 19 03:14:07 2038".
The abbreviations for the days of the week are 'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', and 'Sat'. The abbreviations for the months are
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', and 'Dec'.
Note that the real C library ctime function puts a newline ('
') character at the end of the string that this function does not. Also note
that since the kernel has no concept of timezones, the returned time is always in GMT.
SystemTap Tapset Reference June 2014 FUNCTION::CTIME(3stap)