On Tue, 2008-10-07 at 16:57 -0400, Caron, Chris wrote: > I just have a quick question regarding the amount of storage occupied > by the journals. Is there a common ratio to determine how much space > will be occupied? > Default Journal size is 128MB. > I’m doing very rough map and experimenting with different conditions, > but I can’t seem to get a common mechanism for predicting the usable > storage limit given the number of locks. > > > > Currently we have an 8 node cluster with 9 journals defined (+1 just > in case)… We are awaiting the external storage hardware; but in the > time being I am using exporting iscsi drives from another machine to > work with. 9 * 128MB = 1152MB - which is pretty consistent with your remaining space below. > > > > With 9 locks and creating a 1.75GB partition, I get 655 MB usable from > it…. (roughly calculated ratio: 3.37) > > With 9 locks and creating a 1.50GB partition, I get 393 MB usable from > it…. (roughly calculated ratio: 2.36) > > With 9 locks and creating a 1.25GB partition, I get 131 MB usable from > it…. (roughly calculated ratio: 0.90) > > > > I’m obviously missing a figure during my calculations because the > ratios vary each time… I’d have expected them to be a bit more > constant… > > At the end of the day I want to be able to know ahead of time how much > hard-disk space I need to allocate for ‘X usable’ based on the number > of locks I’m using. > > > > The simple equation I used was: > > X/9=USABLE/ALLOCATED > > > > ie: (X/9=.655/1.75 = 3.369) > > > > > > Chris > > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
