On Feb 24, 2014, at 17:44, Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> wrote:
>
> 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.
BTW: if you don’t want to compile your kernel with module support, then those same parameters can be used on the kernel command line. That provides the same guarantees w.r.t. races...
_________________________________
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
