Hi Chris, Yesterday Chris Worley wrote: > Note that I do have one to experiment with. > What's a good way to measure journal performance, and/or in what cases do > you need a faster journal (i.e. an EXT3 atop an MD device with big block > stripes)? > > Chris Well, the 'problem' we had to solve was the following: setup: - large HW raid6 array - lvm on top - many ext3 partitions when there was a lot of write or meta data update activity on one partition, performance on all other partitions went to 0. (processes hanging for 10-20 seconds as soon as they accessed the filesystem). I am sure that there is a bad-bad bug in the linux kernel somewhere which is causing this, but all the upgrading and patching did not help, the condition remained. Until we moved the journals off to that external ssd. Now I can copy partition A over to partition B and the server remains nicely responsive. I am atributing that to the external journal. Obviously I would like to know how bad we are going to be had when the ssd dies. cheers tobi -- Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland http://it.oetiker.ch tobi@xxxxxxxxxx ++41 62 775 9902 / sb: -9900 _______________________________________________ Ext3-users mailing list Ext3-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/ext3-users
