Tom, In my experience, in last April, a BBWC solution did not accelerate PostgreSQL well. The device which I tried was i-ram by gigabyte (http://techreport.com/reviews/2006q1/gigabyte-iram/index.x?pg=1 ). The i-ram showed only a little performance improvement compared to PostgreSQL with fsync to disk. (However, in then case of PostgreSQL fsync=off, the performance improvement was great). Thus I think Sigres is better than BBWC, to the best of my knowledge.
However, I do not know other BBWC technologies such as HP smart array E200 controller. (http://h18004.www1.hp.com/products/servers/proliantstorage/arraycontrollers/smartarraye200/index.html) So, I am sorry if I describe wrong conclusion. Best Regards, -- Hideyuki Tom Lane wrote: > Gene <[EMAIL PROTECTED]> writes: > >> I was curious to see how postgres would perform with wal on a tmpfs vs disk >> here are some numbers I got from pgbench. Let me know if I did something >> stupid, this is the first time I've used pgbench. The wal on tmpfs method is >> not significantly faster. >> > > This comparison is not very useful because you were using battery-backed > write cache, which gives pretty much all the performance improvement > that is to be looked for in this area. Try it against a plain vanilla > disk drive (that's not lying about write complete) and you'll find the > maximum TPS rate is closely related to the disk's rotation rate. > > At the same time though, the existence of BBWC solutions makes me wonder > why we need another. > > regards, tom lane > > > -- Hideyuki Kawashima (Ph.D), University of Tsukuba, Graduate School of Systems and Information Engineering Assistant Professor, TEL: +81-29-853-5322 ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
