Subject: Re: interactive performance problems
To: Laine Stump <lainestump@rcn.com>
From: Chuck Silvers <chuq@chuq.com>
List: current-users
Date: 12/02/2000 11:12:40
On Fri, Dec 01, 2000 at 01:00:48PM -0500, Laine Stump wrote:
> Also, wrt UBC (I'm guessing), I'm now noticing large interactive
> performance lags while copying large files, which I hadn't seen with
> 1.5_BETA. Also, if I copy a large file (eg 114MB) while I have an
> emacs up, even if I come back to the emacs just a few seconds after
> the copy is done, there is a noticable delay before I can type
> anything. This was not the case before. Is UBC maybe being too
> agressive in its caching, to the detriment of swap for "active"
> processes? Is there an easy way to tune this?

currently we restrict cached file data to about 85% of memory,
so the other 15% would be available for anonymous data.
(it'll be user-adjustible eventually, but not yet.)

what's probably happening for you is that all of the cached pages for
the emacs executable are being reused in favor of the files you're
copying.  I'm planning to change things to also track VTEXT vnode pages
separately from anonymous pages and non-VTEXT vnode pages, which will
hopefully resolve the issues with interactive latency.  I hope to get to
this in the next few weeks.

-Chuck