Re: LOR on nfs: vfs_vnops.c:301 kern_descrip.c:1580

On 18 August 2010 23:11, pluknet <pluknet_at_gmail.com> wrote:
> On 18 August 2010 17:46, Kostik Belousov <kostikbel_at_gmail.com> wrote:
>> On Wed, Aug 18, 2010 at 02:43:19PM +0400, pluknet wrote:
>>> On 18 August 2010 12:07, pluknet <pluknet_at_gmail.com> wrote:
>>> > On 17 August 2010 20:04, Kostik Belousov <kostikbel_at_gmail.com> wrote:
>>> >
>>> >>
>>> >> Also please take a note of the John' suggestion to use the taskqueue.
>>> >
>>> > I decided to go this road. Thank you both.
>>> > Now I do nfs buildkernel survive and prepare some benchmark results.
>>> >
>>>
>>> So, I modified the patch to defer proc_create() with taskqueue(9).
>>> Below is `time make -j5 buildkernel WITHOUT_MODULES=yes` perf. evaluation.
>>> Done on 4-way CPU on clean /usr/obj with /usr/src & /usr/obj both
>>> nfs-mounted over 1Gbit LAN.
>>>
>>> clean old
>>> 1137.985u 239.411s 7:42.15 298.0%       6538+2133k 87+43388io 226pf+0w
>>>
>>> clean new
>>> 1134.755u 240.032s 7:41.25 298.0%       6553+2133k 87+43367io 224pf+0w
>>>
>>> Patch needs polishing, though it generally works.
>>> Not sure if shep_chan (or whatever name it will get) needs locking.
>> As I said yesterday, if several requests to create nfsiod coming one
>> after another, you would loose all but the last.
>>
>> You should put the requests into the list, probably protected by
>> nfs_iod_mtx.
>>
>
> How about this patch? Still several things to ask.
> 1) I used malloc instance w/ M_NOWAIT, since it's called with nfs_iod_mtx held.
> 2) Probably busy/done gymnastics is a wrong mess. Your help is appreciated.
> 3) if (1) is fine, is it right to use fail: logic (i.e. set
> NFSIOD_NOT_AVAILABLE)
> on memory shortage? Not tested.
>
> There are debug printf() left intentionally to see how 3 contexts run under load
> to each other. I attached these messages as well if that makes sense.
>

Ah, yes. Sorry, forgot about that.

This is from last run:
1139.225u 239.873s 7:44.90 296.6%       6524+2130k 77+43153io 220pf+0w

-- 
wbr,
pluknet