Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Fri, Jan 23, 2009 at 05:59:47PM +0100, Bruno Voigt wrote: > Hi, > > I'm looking for some figures: > > What are the memory requirements/guidelines for DRBD resources? > What are the maxima for normal operation, sync, verify ? > Is it dependent on the size of the replicated device? > Does the requirements increase lineary with each resource ? > > I'm playing with a Debian lenny/unstable system pair (HP DL360 G5, 8G RAM) > with linux 2.6.18.6 (or 2.6.26.1), xen 3.2.1, DRBD 8.3.0, > hosting 13 DomU - each with 2 DRBD-Devices (4G disk+512M swap) > allocated from LVM LVs each separately replicated with DRBD. > > The Dom0 got a fixed amount of memory (1 G via grub menu.list > xenhopt=dom0_mem=1024M) > and I've seen the situation that the Out-of-memory killer strikes on the > node A > if all DRBD resources are synced (all at once) from node A to initially > connected node B. > > Nothing else besides an small apache is running on the Dom0, > in disconnected mode there is over 600M available on node a. > > If I sync the resources one by one the OOM can be prevented. > > So I'm looking for a solid based way to size the RAM of the Dom0 .. From: Lars Ellenberg Subject: Re: Summarizing DRBD memory usage Date: 2008-07-24 10:43:52 GMT http://thread.gmane.org/gmane.linux.network.drbd/15482/focus=15485 so in your situation, right, serialize the resync (probably a good idea anyways). and/or maybe decrease "max-buffers", which limits the number of in-flight pages. or give it plenty of ram. -- : Lars Ellenberg : LINBIT | Your Way to High Availability : DRBD/HA support and consulting http://www.linbit.com DRBD® and LINBIT® are registered trademarks of LINBIT, Austria. __ please don't Cc me, but send to list -- I'm subscribed