[mythtv] [mythtv-commits] Ticket #9709: TFW IOBOUND

[Daniel Kristjansson]

On Mon, 2011-05-16 at 21:49 +0000, MythTV wrote:
> #9709: TFW IOBOUND
> -----------------------------------+----------------------------
>  Reporter:  spamme@…               |          Owner:  danielk
>      Type:  Bug Report - General   |         Status:  new
>  Priority:  minor                  |      Milestone:  0.25
> Component:  MythTV - Recording     |        Version:  Trunk Head
>  Severity:  medium                 |     Resolution:
>  Keywords:                         |  Ticket locked:  0
> -----------------------------------+----------------------------
> Comment (by spamme@…):
>  The incoming data rate is about 2000k/s, why does the ThreadedFileWrite
>  write at 64kb per interval???  = FAIL.

>From looking at your logs the main problem is that writes to disk
are taking 10, 30, and 39 seconds on different occasions. This
indicates a hardware failure, some truly awful hardware, or a
very serious configuration problem.

64 KB or smaller writes should cause no problem at all, these are
writes to the OS buffers, not directly to disk. Unless you've done
something silly like mount with the "sync" option these writes
don't even force a write to the metadata log.

-- Daniel