makedumpfile 1.5.0 takes much more time to dump
vgoyal at redhat.com
Wed Oct 3 08:48:13 EDT 2012
On Wed, Oct 03, 2012 at 04:38:35PM +0900, Atsushi Kumagai wrote:
> > > If that's going to take time, can we make using of new logic conditional
> > > on a command line option. So that user has the option of using old
> > > logic.
> > >
> > Kumagai-san should decide this.
> I'm not planning to make the cyclic mode optional.
> However, I think the performance issue should be improved even without
> mem_map array logic.
> So, I will try to reduce the number of cycles as few times as possible for v1.5.1,
> the performance issue will be improved.
> To make sure of it, would you re-test with --cyclic-buffer 32768 (32MB), Vivek ?
> Then the result of v1.5.0 is still too bad, I will consider using the old logic
> as default logic.
Actually chaowang did the testing. In the bug he provided data for 16MB
makedumpfile with 16M cyclic buffer,
#1. makedumpfile-1.5.0 -c --message-level 1 -d 31 --cyclic-buffer 16384
#2. makedumpfile-1.5.0 -E --message-level 1 -d 31 --cyclic-buffer 16384
Which looks much better than default numbers. Chao, can you please do the
testing with 32MB buffer size and provide the data here.
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