Re: io_submit() taking a long time to return ?

> By reading the aio documentation, we expected the io_submit call to
> always return immediately,

Sadly, that isn't guaranteed.

> but in our preliminary tests we noticed that
> sometimes this call can take a long time (more than 10 ms, even
> sometimes more than 30 ms !!).

If I had to guess I'd suspect that these delays are due to sync block
mapping lookups in the submit path.  Do these tend to show up the first
time you read a file?

- z
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

---

• Follow-Ups:
  • Re: io_submit() taking a long time to return ?
    • From: "Raz Ben-Jehuda(caro)" <[email protected]>

• References:
  • io_submit() taking a long time to return ?
    • From: Xavier Roche <[email protected]>

• Prev by Date: Re: [PATCH] Convert idr's internal locking to _irqsave variant
• Next by Date: Re: [patch] lockdep: annotate mm/slab.c
• Previous by thread: io_submit() taking a long time to return ?
• Next by thread: Re: io_submit() taking a long time to return ?
• Index(es):
  • Date
  • Thread

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]