Date: Tue, 24 Nov 2015 08:31:15 -0600 From: Adam Vande More <amvandemore@gmail.com> To: Albert Cervin <albert@acervin.com> Cc: "freebsd-stable@freebsd.org" <freebsd-stable@freebsd.org> Subject: Re: ZFS - poor performance with "large" directories Message-ID: <CA%2BtpaK3czSuxGH0J%2BVyPRfC8CiGJBk_CPf=bwQzxLjM94RCY9A@mail.gmail.com> In-Reply-To: <CAMMK2LCB5ocjyufZCMXQScQDgVxvSHOr0vmef6LKzPO35w3TQg@mail.gmail.com> References: <CAMMK2LCB5ocjyufZCMXQScQDgVxvSHOr0vmef6LKzPO35w3TQg@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, Nov 24, 2015 at 8:00 AM, Albert Cervin <albert@acervin.com> wrote: > Hi all, > > Please feel free to direct me to a list that is more suitable. > > We are trying to set up a fileserver solution for a web application that we > are building. This fileserver is running FreeBSD 10.2 and ZFS. Files are > written over CIFS with Samba running on the fileserver host. > > However, we are seeing en exponential decrease in performance to write to > the file server when the number of files in the directory grows (when it > goes up to ~6000 files it becomes unusable and the write time has gone from > a fraction of a second to ten seconds). > > We ran the same setup on a Linux machine with an ext4 file system which did > NOT suffer from this performance degradation. > I should hope not. ext4 vs zfs comparison isn't fair for either. > > Are these "holes" in write speed normal. Since this is the exact symptom we > are getting when the network writes start to be slow. > Totally normal. You'll want to reference: https://wiki.freebsd.org/ZFSTuningGuide In particular for that issue see: vfs.zfs.txg.timeout and tuning related to NFS. Performance is also heavily dependent on pool structure and io characteristics. For example, a pool of 3 2 disk mirrors is in general going to be much faster than 1 6 disk raidz2. -- Adam
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CA%2BtpaK3czSuxGH0J%2BVyPRfC8CiGJBk_CPf=bwQzxLjM94RCY9A>