[Devel] [PATCH hci-8.1] fs/fuse kio: start connect once per rpc_queue_work batch

Alexey Kuznetsov kuznet at virtuozzo.com
Tue Sep 22 16:12:51 MSK 2026


Hello!

On Tue, Sep 22, 2026 at 7:41 PM Vladimir Riabchun
<vladimir.riabchun at virtuozzo.com> wrote:
> These were just my thoughts if we can heal the stuck thread with
> low effort. Seems like no - at least we need to drop these
> assertions.

I do not see any problems there. Well, except for too scary code.
If you see, elaborate, I could miss something.

> To prevent cases like the one below - inconsistent code state.

IMHO it prevents nothing. It just minimizes patch success. :-)
Is it correct that all these kludges are done to avoid stop machine?
Or is it still used? Sleeping states must be responsibility of patch maker,
protections based on traces are  just useless, kernel simply cannot do it
by many reasons f.e. because of tail calls.

> Btw, I'm just curious, how iptables rule will help? It will tesspeed up pcs_rpc_connect?

Yes, almost infinitely. In the last case we had 16 dead rpcs, each has
queued 200000-300000
requests. Each connect waits for ~2sec. So, counting: it would take
~75 days to finish. :-)
With -j DROP they were processed faster than I started drgn to measure
the rate, some
seconds.



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