Re: Swap or I/O Improvement in Fedora 8?

"LaBird" <b_cheung_2005@xxxxxxxxx> wrote in
news:fq7vn0$p6a$1@xxxxxxxxxxxxxxxxx:

I just have a few preliminary findings in running a large application
using 16GB memory.

On Fedora 8 (Kernel 2.6.23-1.42), it runs using less than 2 hours to
complete only when
I first login as root, and then "su" to a normal user to run the
program. However, if I directly login as the same normal user, the
program takes about 9 hours to complete.

Is there any difference in the memory management for 2.6.21 and
2.6.23, and why logging as a root user first will reduce the execution
time by that much in 2.6.23? Thanks in advance.

It's really impossible to say without more information. But the chief
difference between logging in as root then su'ing to a user and simply
logging in as that user is in the environment strings (as shown by the env
command). Investigate what happens if you use "su - user" which causes su
to invoke a "login shell" (which really just means that the shell processes
a different set of initial script files).

GH
.

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