Re: [BENCHMARK] max bomb segment tuning with read latency 2 patchin

[Andrew Morton]

GrandMasterLee wrote:
> 
> ...
> One interesting thing about my current setup, with all scsi or FC disks,
> is that bomb never displays > 0.
> Example:
> 
> elvtune /dev/sdn yields:
> 
> /dev/sdn elevator ID            17
>         read_latency:           8192
>         write_latency:          16384
>         max_bomb_segments:      0
> 
> elvtune -b 6 /dev/sdn yields:
> 
> /dev/sdn elevator ID            17
>         read_latency:           8192
>         write_latency:          16384
>         max_bomb_segments:      0
> 
> Is it because I just do volume management at the hardware level and use
> whole disks? Or is that something else?

You need a patched kernel.  max_bomb_segments is some old thing
which isn't implemented any more.  But I reused it for something
completely different in the patch which Con is testing.  So I
wouldn't have to futz around with patching userspace apps.