11 reputation
2
bio website
location
age
visits member for 9 months
seen Dec 2 at 15:23

Mar
13
revised Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
added 584 characters in body
Mar
7
comment Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
I have disabled prefetch and I am testing again.
Mar
7
comment Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
On one system with 8GB of memory regular filesystems cache the whole working data set. On a system with 16GB of RAM and 12GB arc, zfs is still reading from the disk and has not cached all of the working data. The size of the ARC on all systems tested is greater than the size of the data read by the test program.
Mar
7
comment Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
I do disable atime on all the filesystems where that is an option, but it was a good suggestion. It would seem that setting primarycache to metadata would cause zfs to cache even less than it currently does but since it costs me nothing but time to try it, I probably will.
Mar
6
awarded  Student
Mar
6
revised Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
added 502 characters in body
Mar
6
revised Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
added 502 characters in body
Mar
6
revised Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
added 502 characters in body
Mar
6
awarded  Editor
Mar
6
revised Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
added 153 characters in body
Mar
6
comment Why does zfs fail to cache this workload when “normal” filesystems cache it completely?
So scanning a bunch of files and reading data from them is a desktop workload? It certainly seems to me that this workload would be a lot like a Maildir/IMAP server. The files are slightly larger but the amount of data read from each one is small in both cases. This was tested on Xeon systems with ECC memory although the hard drives were SATA drives.
Mar
6
asked Why does zfs fail to cache this workload when “normal” filesystems cache it completely?