Hmm - I wonder what OS it runs ;-) - Luke ----- Original Message ----- From: david@xxxxxxx <david@xxxxxxx> To: Luke Lonergan Cc: glynastill@xxxxxxxxxxx <glynastill@xxxxxxxxxxx>; pgsql-performance@xxxxxxxxxxxxxx <pgsql-performance@xxxxxxxxxxxxxx> Sent: Fri Jan 23 04:52:27 2009 Subject: Re: SSD performance On Fri, 23 Jan 2009, Luke Lonergan wrote: > Why not simply plug your server into a UPS and get 10-20x the > performance using the same approach (with OS IO cache)? > > In fact, with the server it's more robust, as you don't have to transit > several intervening physical devices to get to the RAM. > > If you want a file interface, declare a RAMDISK. > > Cheaper/faster/improved reliability. you can also disable fsync to not wait for your disks if you trust your system to never go down. personally I don't trust any system to not go down. if you have a system crash or reboot your RAMDISK will loose it's content, this device won't. also you are limited to how many DIMMS you can put on your motherboard (for the dual-socket systems I am buying nowdays, I'm limited to 32G of ram) going to a different motherboard that can support additional ram can be quite expensive. this isn't for everyone, but for people who need the performance, data reliability, this looks like a very interesting option. David Lang > - Luke > > ----- Original Message ----- > From: pgsql-performance-owner@xxxxxxxxxxxxxx <pgsql-performance-owner@xxxxxxxxxxxxxx> > To: Glyn Astill <glynastill@xxxxxxxxxxx> > Cc: pgsql-performance@xxxxxxxxxxxxxx <pgsql-performance@xxxxxxxxxxxxxx> > Sent: Fri Jan 23 04:39:07 2009 > Subject: Re: SSD performance > > On Fri, 23 Jan 2009, Glyn Astill wrote: > >>> I spotted a new interesting SSD review. it's a $379 >>> 5.25" drive bay device that holds up to 8 DDR2 DIMMS >>> (up to 8G per DIMM) and appears to the system as a SATA >>> drive (or a pair of SATA drives that you can RAID-0 to get >>> past the 300MB/s SATA bottleneck) >>> >> >> Sounds very similar to the Gigabyte iRam drives of a few years ago >> >> http://en.wikipedia.org/wiki/I-RAM > > similar concept, but there are some significant differences > > the iRam was limited to 4G, used DDR ram, and used a PCI slot for power > (which can be in > short supply nowdays) > > this new drive can go to 64G, uses DDR2 ram (cheaper than DDR nowdays), > gets powered like a normal SATA drive, can use two SATA channels (to be > able to get past the throughput limits of a single SATA interface), and > has a CF card slot to backup the data to if the system powers down. > > plus the performance appears to be significantly better (even without > using the second SATA interface) > > David Lang > > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance > -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)To make changes to your subscription:http://www.postgresql.org/mailpref/pgsql-performance
