Use nocache program to bypass page cache

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Has anybody tested the nocache program?https://github.com/Feh/nocache
My test (on RHEL 8.3) shows it's doing what it claims:
$ grep Cache /proc/meminfo
Cached:         14119024 kB
SwapCached:          544 kB
$ grep Cache /proc/meminfo
Cached:         14119044 kB
SwapCached:          544 kB
$ ./nocache cp $ORACLE_HOME/bin/oracle .
$ grep Cache /proc/meminfo
Cached:         14119308 kB
SwapCached:          544 kB
$ cp $ORACLE_HOME/bin/oracle .
$ grep Cache /proc/meminfo
Cached:         14553412 kB
SwapCached:          544 kB
$ ll oracle
-rwxr-x--x 1 oracle oinstall 444390704 Jul 15 13:34 oracle
Basically, I copied a 400 MB file (19c Oracle server binary $ORACLE_HOME/bin/oracle). Using nocache, Page Cache size barely increased, probably due to fluctuations on this live server, and partly due to metadata usage of this cp command. But not using nocache, Page Cache usage went up by about the size of this binary file. I plan to use this program on many of our servers (just two files, nocache and nocache.so, are really needed on other servers once you make'd on one server running this version of OS). I think this is better than trying to mount a file system with direct I/O support (if you finally get it supported), because using this program you still generally benefit from Page Cache and consciously make a decision when running a specific program whether to cache the file content. I wish Red Hat officially supported this program, or one similar to this. What do you all think?

Yong
-- 
redhat-list mailing list
unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe
https://listman.redhat.com/mailman/listinfo/redhat-list




[Index of Archives]     [CentOS]     [Kernel Development]     [PAM]     [Fedora Users]     [Red Hat Development]     [Big List of Linux Books]     [Linux Admin]     [Gimp]     [Asterisk PBX]     [Yosemite News]     [Red Hat Crash Utility]


  Powered by Linux