Re: [ckrm-tech] [PATCH] BC: resource beancounters (v4) (added usermemory)

From: Balbir Singh
Date: Mon Sep 18 2006 - 07:28:20 EST


Pavel Emelianov wrote:
Kirill Korotaev wrote:

[snip]
I have a C program that computes limits to obtain desired guarantees
in a single 'for (i = 0; i < n; n++)' loop for any given set of guarantees.
With all error handling, beautifull output, nice formatting etc it weights
only 60 lines.

Look at http://wiki.openvz.org/Containers/Guarantees_for_resources
I've described there how a guarantee can be get with limiting in details.

[snip]

I do not 'do not like guarantee'. I'm just sure that there are two ways
for providing guarantee (for unreclaimable resorces):
1. reserving resource for group in advance
2. limit resource for others
Reserving is worse as it is essentially limiting (you cut off 100Mb from
1Gb RAM thus limiting the other groups by 900Mb RAM), but this limiting
is too strict - you _have_ to reserve less than RAM size. Limiting in
run-time is more flexible (you may create an overcommited BC if you
want to) and leads to the same result - guarantee.
I think this deserves putting on Wiki.
It is very good clear point.

This is also on the page I gave link at.


The program (calculate_limits()) listed on the website does not work for
the following case

N=2;
R=100;
g[2] = {30, 30};


The output is -10 and -10 for the limits

For

N=3;
R=100;
g[3] = {30, 30, 10};

I get -70, -70 and -110 as the limits

Am I interpreting the parameters correctly? Or the program is broken?

--

Balbir Singh,
Linux Technology Center,
IBM Software Labs
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/