On Fri, Nov 14, 2014 at 4:35 PM, Dan van der Ster <daniel.vanderster@xxxxxxx> wrote: > Hi Greg, > > On Fri Nov 14 2014 at 4:07:41 PM Gregory Farnum <greg@xxxxxxxxxxx> wrote: >> >> On Fri, Nov 14, 2014 at 6:24 AM, Joaquim Rocha <joaquim.rocha@xxxxxxx> >> wrote: >> > Hi folks, >> > >> > I found out recently that xattributes are limited to 100 chars in length >> > so >> > I saw the commits that introduced this change [1] but I don't understand >> > why >> > this is needed if we take into account that by default xattributes are >> > going >> > into the omap. >> > >> > In those changes it also prevents that limit to go over 100 even >> > configured >> > that way so I would like to know the reason for this limit and if there >> > is >> > any other way we can override it I might be missing. >> > >> > For my use case I will need a much larger length so I think that there >> > should be a way to easily increase the limit (or even have a much larger >> > value as the default). >> > >> > [1] https://github.com/ceph/ceph/pull/2111 >> >> These are just setting limits on the length of the xattr *names*, not >> the xattr contents. This is because filesystems impose limits on name >> size and we do store xattrs in the filesystem in the default >> configuration with most releases of Ceph (they overflow into leveldb >> if there are too many). >> If that's really going to be a problem for you...I don't know what to >> say, sorry. These are close to limits you should have been following >> already fi you want your stuff to work on e.g. ext4. :) > > > > Do you know where the limits are? This limitation was a surprise to us > because with latest dumpling on RHEL6.6 XFS we can set and get very long > xattr names. IOW, we cannot reproduce the truncation issue reported by > yuyuyu in #2111. With a new object asdf we set the first xattr and it > already overflowed into the omap. > Nevermind, I realized this is because we had filestore_max_inline_xattrs = 2. With filestore_max_inline_xattrs = 5 for example, I can reproduce the truncation issue. Cheers, Dan -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
