rsync daemon caching/memory usage?

Matt Garman garman at
Thu May 29 10:15:23 EST 2003

I have two computers: a Linux box which I use as my workstation
(day-to-day use) and an OpenBSD box which I designate for server tasks:
gateway, firewall, etc.

I use rsync to mirror many gigs worth of data from the Linux box
(running rsync in daemon mode) to the OpenBSD machine (running an rsync
client job nightly).

Since the amount of data and the number of files that I mirror is great,
most of rsync's time seems to be spent computing differences in the
files.  This appears to put quite a burden on the Linux workstation.
The result, I belive, is that much of the Linux box's memory is consumed
caching all this information that it is processing.

The reason I think this is because the apps I left running (e.g.  file
browser, Mozilla, gnumeric spreadsheets, etc) need a few seconds to
"wake up" when they are first used for the day (subsequent use meets no
delays).  My theory is that most of my RAM is consumed in caching the
rsync nightly job, and my actual apps are swapped out.

At one GB, I have WAY more RAM than I need for my actual work, yet it
seems like I'm not really benefitting from having this kind of memory
(at least initially).

Maybe I'm just making too big a deal out of this <grin> but is there any
way to have rsync not allow itself to be cached, or maybe to force it to
use a disk cache instead of physical RAM?  Since this jobs runs at night
when I'm not using the computer, I don't care about degrading rsync's


Matt Garman, garman at
``I ain't never seen no whiskey, the blues made my sloppy drunk!''
        -- Sleepy John Estes, ``Leaving Trunk''

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