On Sun, Nov 15, 2020 at 02:57:49PM -0500, Kenneth Gober wrote:
> On Sun, Nov 15, 2020 at 8:59 AM Mischa <obs...@high5.nl> wrote:
>
> > On 15 Nov at 14:52, Otto Moerbeek <o...@drijf.net> wrote:
> > > fsck wil get slower once you start filling it, but since your original
> > > fs had about 104k files it expect it not getting too bad. If the speed
> > > for your usecase is good as well I guess you should be fine.
> >
> > Will see how it behaves and try to document as much as possible.
> > I can always install another BSD on it. ;)
> >
>
> To give a very rough idea, here is a sample running fsck on an FFS2
> file system with a fairly large number of files:
>
>
> $ df -ik /nfs/archive
>
> Filesystem 1K-blocks Used Avail Capacity iused ifree %iused
> Mounted on
>
> /dev/sd1g 12308149120 7477490128 4215251536 64% 4800726 383546408
> 1% /nfs/archive
>
> $ doas time fsck -f /nfs/archive
>
> ** /dev/sd1g (6d3438729df51b22.g) (NO WRITE)
>
> ** Last Mounted on /nfs/archive
>
> ** Phase 1 - Check Blocks and Sizes
>
> ** Phase 2 - Check Pathnames
>
> ** Phase 3 - Check Connectivity
>
> ** Phase 4 - Check Reference Counts
>
> ** Phase 5 - Check Cyl groups
>
> 4800726 files, 934686266 used, 603832374 free (35534 frags, 75474605
> blocks, 0.0% fragmentation)
> 3197.25 real 35.86 user 66.03 sys
>
> This is on older hardware, and not running the most recent release.
> The server is a Dell PowerEdge 2900 with a PERC H700 controller, and
> 4 WD Red Pro 8TB disks (WD8001FFWX-6) forming a RAID10 volume
> containing 3 small 1TB file systems and 1 large 12TB file system. The
> OS is OpenBSD 6.1/amd64. All the file systems on this volume are
> mounted with the softdep option and the big one has noatime as well.
If you upgrade; there's a good chance fskc wil be faster.
-Otto
>
> The time to run fsck is really only an issue when the server reboots
> unexpectedly (i.e. due to a power outage). Coming up after a proper
> reboot or shutdown is very fast due to the file systems being clean.
> A UPS can help avoid most of these power-related reboots. Alas, this
> particular server was connected to a UPS with a bad battery so it has
> rebooted due to power outages at least a half-dozen times this year,
> each of them involving a fairly long fsck delay. I finally took the time
> last week to replace the UPS batteries so going forward this should
> be much less of a problem. I do recommend the use of a UPS (and
> timely replacement of batteries when needed) if you are going to
> host very large FFS2 volumes.
>
> I have never lost files due to a problem with FFS2 (or with FFS for that
> matter), but that is no reason not to perform regular backups. For this
> particular file system I only back it up twice a year, but the data on it
> doesn't change often. File systems with more 'normal' patterns of usage
> get backed up weekly. The practice of taking regular backups also helps
> ensure that 'bit rot' is detected early enough that it can be corrected.
>
> -ken
