From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cyril Hrubis Date: Thu, 19 May 2016 15:38:54 +0200 Subject: [LTP] [RFC PATCH 4/4] memcg_stress_test.sh: allocate less than CommitLimit bytes In-Reply-To: <573CA66F.9000900@oracle.com> References: <1461338590-1309-1-git-send-email-stanislav.kholmanskikh@oracle.com> <1461338590-1309-2-git-send-email-stanislav.kholmanskikh@oracle.com> <1461338590-1309-3-git-send-email-stanislav.kholmanskikh@oracle.com> <1461338590-1309-4-git-send-email-stanislav.kholmanskikh@oracle.com> <20160512134217.GB32457@rei.lan> <573B140B.8080500@oracle.com> <20160518143918.GB17880@rei.lan> <573CA66F.9000900@oracle.com> Message-ID: <20160519133854.GC29601@rei.lan> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it Hi! > > I guess that when we decide to create the pressure inside of the memory > > cgroup, instead of stressing the whole system, we may as well choose > > small enough amount of memory, something as (RAM - 250Mb)/10 and be done > > with it. > > Yes, this should work as well. > > I don't know how we could stress the whole system without the risk of > hitting an OOM. One idea which comes to my mind is about using a > top-level control group with a significant amount of memory assigned to > it (like mem_free / 2). > > Could you, please, have a look at the attachment? I was playing with > this patch today and was able to stress my system without OOM. > > However, this scheme may result in a very intensive swapping if mem_free > is large (given that there is enough swap). Then we should place upper limit on the amount of used swap as well. Something as MIN(MemFree/2, SwapFree, 1GB) to be used for the limit and abort the test if this number is to small? Apart from that the root memory cgroup should be better named something as ltp_stres_root so that it's clear where it came from... -- Cyril Hrubis chrubis@suse.cz