Raise high, low, and oom watermarks

Matt Ingenthron added a comment - 07/Jan/13 2:16 PM Why? I'd be a little concerned with this based on what we've seen in recent reports. For example, workload remains constant, compaction kicks in, IO goes away, and we exhaust memory sending TMPOOM to clients.

Mike Wiederhold added a comment - 07/Jan/13 2:22 PM This is based on the tests the performance team has done. Also, how would raising these limits hurt the scenario you mentioned? We add the size of the cache and the size of the internals (including persistence queues). It seems like this would just allow users to utilize more memory and this really comes down to whether or not our memory accounting is good enough to keep from swapping memory to disk.

Perry Krug added a comment - 07/Jan/13 4:04 PM My 2 cents: -suggest 80/85/95 as percentages (raise the low a bit, and also shrink the distance between low and high which is a range for a potentially large number of ejections when the high is tripped) -highly suggest (and ask for) not using only percentages but also having absolute values when applied to larger RAM systems. 85% of 128GB is "wasting" almost 20GB of data on each node...a 10 node system will have 200GB of RAM that can never be used. Whereas if we use whichever is lower of 5/3/2GB or 80/85/95% we will make the system much more flexible for lower RAM and higher RAM setups.

Mike Wiederhold added a comment - 07/Jan/13 7:43 PM These are very easy to change later. Per the request of the performance team I am going to set them to 75/85/95 for now, but I agree we should revisit the issue before we hit the code complete date.

Farshid Ghods added a comment - 09/Jan/13 8:29 PM Mike, is this change merged ?

Mike Wiederhold added a comment - 09/Jan/13 8:35 PM It will be tomorrow morning.

Perry Krug added a comment - 11/Jan/13 11:18 AM Can we re-open this for looking at percentage vs absolute value settings? I really think it's hurting us in larger RAM-sized systems

Mike Wiederhold added a comment - 11/Jan/13 12:11 PM We already have another bug files for that and I plan on pushing product management to make this change for 2.1.

Perry Krug added a comment - 11/Jan/13 12:14 PM Thanks Mike...did I miss that bug somewhere? Would you mind sending it over?

Mike Wiederhold added a comment - 13/Jan/13 3:57 PM The bug is filed under MB-4370 .

Thuan Nguyen added a comment - 17/Jan/13 4:04 PM Integrated in github-ep-engine-2-0 #475 (See [ http://qa.hq.northscale.net/job/github-ep-engine-2-0/475/ ])      MB-7498 : Change high and low watermarks to 85 and 75 respectively (Revision 40544dd94cc758f94e86eb37f0af9135671fc56a)      Result = SUCCESS Mike Wiederhold : Files : * src/ep_engine.cc * configuration.json * tests/ep_testsuite.cc

Thuan Nguyen added a comment - 14/Feb/13 10:45 PM Integrated in github-ep-engine-2-0 #477 (See [ http://qa.hq.northscale.net/job/github-ep-engine-2-0/477/ ])      MB-7498 : Change high and low watermarks to 85 and 75 respectively (Revision 40544dd94cc758f94e86eb37f0af9135671fc56a)      Result = SUCCESS Mike Wiederhold : Files : * src/ep_engine.cc * tests/ep_testsuite.cc * configuration.json