> From: zfs-discuss-boun...@opensolaris.org [mailto:zfs-discuss- > boun...@opensolaris.org] On Behalf Of Arne Jansen > > There is absolutely no sense in having slog devices larger than > then main memory, because it will never be used, right?
Also: A TXG is guaranteed to flush within 30 sec. Let's suppose you have a super fast device, which is able to log 8Gbit/sec (which is unrealistic). That's 1Gbyte/sec, unrealistically theoretically possible, at best. You do the math. ;-) That being said, it's difficult to buy an SSD smaller than 32G. So what are you going to do? Slice it and use the remaining space for cache? Some people do. Some people may even get a performance benefit by doing so. But if you do, now you've got a cache and a log both competing for IO on the same device. The performance benefit degrades for sure. My advice is to simply acknowledge wasted space in your log device, forget about it and move on. Same thing you did with all the wasted space on your mirrored OS boot device, which can't (or shouldn't) be used by your data pool. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
