We're looking at getting an HBR (that's a technical term, honkin'
big
RAID). What I'm considering is, rather than chopping it up into 14TB or
16TB filesystems, of using xfs for really big filesystems. The question
that's come up is: what's the state of xfs on CentOS6? I've seen a
number
of older threads seeing problems with it - has that mostly been resolved?
How does it work if we have some *huge* files, and lots and lots of
smaller files?
mark
On 2014-05-28, m.roth at 5-cent.us <m.roth at 5-cent.us> wrote:> We're looking at getting an HBR (that's a technical term, honkin' big > RAID). What I'm considering is, rather than chopping it up into 14TB or > 16TB filesystems, of using xfs for really big filesystems. The question > that's come up is: what's the state of xfs on CentOS6? I've seen a number > of older threads seeing problems with it - has that mostly been resolved?I have some largish (>20TB) xfs filesystems on CentOS 6, and things seem fine. The one issue I had, quite a while ago (and maybe even in CentOS 5?), was with growing the fs, but I grew one on CentOS 6 recently with no problems.> How does it work if we have some *huge* files, and lots and lots of > smaller files?Define "huge". It seems fine for our use with multi-dozen-GB files (possibly getting to >100GB files) and many small files, but our load is generally not that heavy. --keith -- kkeller at wombat.san-francisco.ca.us
----- Original Message ----- | We're looking at getting an HBR (that's a technical term, honkin' big | RAID). What I'm considering is, rather than chopping it up into 14TB | or | 16TB filesystems, of using xfs for really big filesystems. The | question | that's come up is: what's the state of xfs on CentOS6? I've seen a | number | of older threads seeing problems with it - has that mostly been | resolved? | How does it work if we have some *huge* files, and lots and lots of | smaller files? | | mark | It works well and will be the default for RHEL 7, so that should say something. However, with respect to file system size. Be prepared to have a lot of memory for a file system that is large and a lot of files should you ever need to do a file system check. ;) -- James A. Peltier Manager, IT Services - Research Computing Group Simon Fraser University - Burnaby Campus Phone : 778-782-6573 Fax : 778-782-3045 E-Mail : jpeltier at sfu.ca Website : http://www.sfu.ca/itservices To be original seek your inspiration from unexpected sources.
On 5/28/2014 11:13 AM, m.roth at 5-cent.us wrote:> We're looking at getting an HBR (that's a technical term, honkin' big > RAID). What I'm considering is, rather than chopping it up into 14TB or > 16TB filesystems, of using xfs for really big filesystems. The question > that's come up is: what's the state of xfs on CentOS6? I've seen a number > of older threads seeing problems with it - has that mostly been resolved? > How does it work if we have some*huge* files, and lots and lots of > smaller files?I've had good luck with XFS file systems of 80TB or so for nearline archival storage. thats 36 3TB SAS drives organized as 3 x 11 raid6+0 with 3 hotspares. found two minor(?) gotchas so far with XFS 1) NFS doesn't like 64bit inodes. you can A) only nfs share the root of the giant XFS file system (this *is* the traditional way, but people from a Windows background seem to like to micromanage their shares), or B) use UUID exports (not compatible with all nfs clients in my experience), or C) specify fsid=NNN for a arbitrary unique NNN for each export on a given server. We opted for C. 2) I just discovered the other night that KVM doesn't like booting disk image files stored on xfs on a 4K sector device (in my case, this was an SSD). solution was to specify cache=writeback, which somehow bypasses O_DIRECT. There's probably other fixes, but that works well enough. also, there was a bad kernel in 6.3 or something, that had a serious bug with XFS. the fix came out 2-3 weeks after 6.3 was released, but I ran into internal operations people who don't update production systems, if you say you tested something on 6.3, then they use 6.3 forever. They pathologically skip my installation step 2, "yum -y update". -- john r pierce 37N 122W somewhere on the middle of the left coast