Page 1 of 1

-t0 option for par2

Posted: June 3rd, 2008, 2:40 pm
by neilt0
The multicore par2 thrashes my hard drive when verifying and is a lot slower than single-core par2 in verify passes for large RARs (50 or 100MB+).
Repairing is much faster multi-threaded, but for this reason, the -t0 option was added to TBB par2 (which I assume you're using?).
http://chuchusoft.com/par2_tbb/index.html

-t0 uses one thread to verify and then multiple threads to repair, which is the best option for my machine (2.4GHz Core2 Duo, 2GB RAM, SATA 7200RPM, XP)

Any chance you can add the t0 option (even if not in the interface, in the ini would be fine).

Thanks!

Re: -t0 option for par2

Posted: June 4th, 2008, 1:58 am
by shypike
Maybe it's best to put the -t0 in always.
Is there any gain in using multi-core verification, as it is mostly disk-bound?

I must admit that I did not give that much thought when I added the new par2.

Re: -t0 option for par2

Posted: June 4th, 2008, 11:47 am
by bpwats
Actually, it is not a good idea to put in -t0 always: in my case, it makes things worse.
I use a 2008 Mac Pro with it's standard startup drive (WDC WD3200AAJS S-ATA) running SABnzbD from source.
Typically, i download about 90 files of 50MB file size.

Repairing with -t0 new par2 64bits TBB

real 1m22.677s
user 1m9.813s
sys 0m4.884s

Repairing with -t+ new par2 64bits TBB

real 1m8.906s
user 1m14.471s
sys 0m5.303s

Verification time is worse than MacParDeluxe, which uses just under a minute.
However, the TBB-version performes much better in repairing. I reported this to chuchusoft about a month ago.

Re: -t0 option for par2

Posted: June 4th, 2008, 1:02 pm
by shypike
I'm adding a field in Config->Switches where you type in your own option ( -t- -t0 -t+ ).
Default is empty (so default behaviour).
Not ideal, but it's something.

Re: -t0 option for par2

Posted: June 4th, 2008, 1:19 pm
by neilt0
Thank you!

Much appreciated.