Messages in this thread |  | | Date | Tue, 18 Sep 2001 13:02:27 -0700 | From | Andrew Morton <> | Subject | Re: 2.4.10-pre11: alsaplayer skiping during kernel build (-pre10 did not) |
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Andrea Arcangeli wrote: > > I now have an update ready for Linus to merge that should fix the few > leftovers I had in the very first release of the vm rewrite but of > course I will be interested to hear about any regression/progression > about those changes, I'll post them in a few minutes in CC to l-k. >
Please include Andi's likely()/unlikely() change - it's nice.
I can't measure any obviously new causes of latency in your VM. It's nice that you've paid attention to this in various places.
The main culprits now are the file IO and dirty buffer writeout paths: up to fifty milliseconds in each.
I suggest you stick scheduling points in generic_file_read(), generic_file_write() and write_locked_buffers() and then dispose of the copy-user-latency patch from -aa kernels.
With the above fixed, the main source of latency is /proc/meminfo->si_swapinfo(). It's about five milliseconds per gig of swap, which isn't too bad. But it's directly invokable by userspace (ie: /usr/bin/top) and really should be made less dumb. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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