On Tue, 2005-07-26 at 11:34 -0500, John A Meinel wrote: > I saw a review of a relatively inexpensive RAM disk over at > anandtech.com, the Gigabyte i-RAM > http://www.anandtech.com/storage/showdoc.aspx?i=2480 > > Basically, it is a PCI card, which takes standard DDR RAM, and has a > SATA port on it, so that to the system, it looks like a normal SATA drive. > > The card costs about $100-150, and you fill it with your own ram, so for > a 4GB (max size) disk, it costs around $500. Looking for solid state > storage devices, the cheapest I found was around $5k for 2GB. > > Gigabyte claims that the battery backup can last up to 16h, which seems > decent, if not really long (the $5k solution has a built-in harddrive so > that if the power goes out, it uses the battery power to copy the > ramdisk onto the harddrive for more permanent storage). > > Anyway, would something like this be reasonable as a drive for storing > pg_xlog? With 4GB you could have as many as 256 checkpoint segments.
I haven't tried this product, but the microbenchmarks seem truly slow. I think you would get a similar benefit by simply sticking a 1GB or 2GB DIMM -- battery-backed, of course -- in your RAID controller. -jwb ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq