On Feb 24, 2014, at 17:37, NeilBrown <neilb@xxxxxxx> wrote:
> On Thu, 20 Feb 2014 08:11:47 -0500 Trond Myklebust
> <trond.myklebust@xxxxxxxxxxxxxxx> wrote:
>
>>
>> On Feb 20, 2014, at 1:36, Neil Brown <neilb@xxxxxxx> wrote:
>>
>>> There are a number of NFS-related setting that currently must be set
>>> by writing to various files under /proc.
>>> This is a bit clumsy, particularly for systemd unit files.
>>>
>>> So this series adds options to a number of commands where relevant.
>>>
>>> The first two (rdma, and nfsv4{grace,lease}time) I am quite comfortable with.
>>> The third (nlm grace time) I think is probably right but if someone can argue
>>> an alternate approach I'm unlikely to resist.
>>> The fourth is .... uhm. You better look yourself.
>>>
>>> Part of me thinks that nlm port numbers should be set in /etc/sysctl.conf (or sysctl.d)
>>> and /etc/modprobe.d should have something like
>>>
>>> install lockd sysctl -p /etc/sysctl.d/lockd
>>>
>>> but last time I tried that it broke "modprobe --show-depends".
>>> Also it is awkward to get setting from /etc/sysconfig/nfs into /etc/sysctl.d/lockd
>>>
>>> Thoughts?
>>
>> Why not just do most of this at module load time with something like "modprobe lockd lockd.nlm_grace_period=<nsecs> lockd.nlm_tcpport=<portnr> …”?
>> Better yet, add/edit appropriate entries in /etc/modprobe.conf.d at system setup time.
>>
>
> Adding entries to /etc/modprobe.conf.d doesn't help if nfs is compiled in to
> the base kernel.
> Conversely, adding entries to /etc/sysctl.d doesn't help if nfs is a module.
> You could conceivable do both (for those few values that are available both
> as module parameters and sysctl settings) but that is clumsy and error prone.
>
All the NFS sysctl settings now have module parameter equivalents.
Note that systemd can also override using the /sys/module interface, but the problem with both sysctl and /sys/module is that they get set _after_ the module has been loaded, and hence there is plenty of potential for races with mount requests.
> Your argument could equally well apply to setting the NFS versions that nfsd
> supports, but we have explicit command-line arguments for that.
>
> Due to the highly ad-hoc collection of configuration settings and different
> ways to set them and rules for when they are set, I think it is best to have
> the settings imposed by code we control rather than requiring a similarly
> ad-hoc collection of additions to various configuration files in various
> directories.
See above. The races are the reason why I switched from sysctl to module params.
> Ultimately I would like all nfs-utils daemons to take settings out
> of /etc/sysconfig/nfs (either by reading it directly, or having systemd/bash
> load it into the environment, then the utils using getenv()), so that one
> file (which multiple distros already work with) can configure most of
> nfs-utils. This is a step in that direction with (I think) immediate rewards.
>
> Thanks,
>
> NeilBrown
_________________________________
Trond Myklebust
Linux NFS client maintainer, PrimaryData
trond.myklebust@xxxxxxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
