ZFS compression and filesystem cache
Posted by Doomshammer
on Tuesday, December 19. 2006
at 19:12
in Anwendungen, Computer, English only, Linux/Unix, Privat, Thoughts
Even if the data I used in this example isn't reasonable, the result is pretty impressive though:Creation of a 1 GiB file w/o zfs compression/filesystem cache:
QUOTE:
[root@exitus ~pgsql]# time mkfile 1g foo.1g
mkfile 1g foo.1g 0.07s user 7.81s system 8% cpu 1:27.90 total
mkfile 1g foo.1g 0.07s user 7.81s system 8% cpu 1:27.90 total
After doing a "zfs set compression=on data/postgresql":
QUOTE:
[root@exitus ~pgsql]# time mkfile 1g foo.1g
mkfile 1g foo.1g 0.07s user 7.27s system 58% cpu 12.632 total
mkfile 1g foo.1g 0.07s user 7.27s system 58% cpu 12.632 total
More CPU usage (by the filesystem cache) but the write operation was 6 times faster as it was performed in memory before the physical write operation has been performed.
