Re: [Sks-devel] dump

[Jeffrey Johnson]

On Nov 5, 2011, at 10:35 PM, John Clizbe wrote:

> Robert Hinson wrote:
>> How long does it take to make a dump?
> 
> Depends on how fast you can write to disk. Takes about 90-100 minutes on my
> ATA/100 mirror. haven't timed it in quite a while.
> 

hint: If you're purely limited by write I/O speed, try mmap(2)
and do this on the output buffer:

        xx = madvise(mapped, nmapped, MADV_DONTNEED);

Use one single buffer per-dump file, fill sequentially.

OTOH, I suspect you will find some other bottlenecks to dumping than I/O.

hth

73 de Jeff