I understand this, but I need the space. I have databases that are over 3TB and my customers don't want to pay. I just need to get the biggest bang for my customers bucks. I know you get what you pay for. I just didn't expect the 3ware cards to perform so bad. I think I would have been better off with 4 SATA controllers in the system and do software raid. For my customers that will pay the big $$$, I am using SCSI raid controllers from ICP (now Intel I believe). I am switching all of my 3ware controllers over to Adaptec SATA raid controllers. I am getting better performance with them. Jim ---------- Original Message ----------- From: Mikael Abrahamsson <swmike@xxxxxxxxx> To: Jim Buttafuoco <jim@xxxxxxxxxxxxxx> Cc: linux-raid@xxxxxxxxxxxxxxx Sent: Sat, 31 Jul 2004 10:49:00 +0200 (CEST) Subject: Re: 1x 3ware controllers vs. 2x 3ware controllers > On Fri, 30 Jul 2004, Jim Buttafuoco wrote: > > > I have a dual XEON 3.2 Ghz system 12 G of ram with a 3ware 8506-8 in it > > (8 250 G drives). The hard raid performance was very bad. with the > > load avg going over 40. I then switched over to JBOD and software raid. > > The IO wait times are really high and the performance sucks. Very hard > > to explain to my boss where the $20k went. The system is a database > > server (postgres). I tried both kernel 2.4 and 2.6 with the same > > problem. I am now in the process of testing the adaptec raid > > controller. > > You should never ever ever use raid5 with something that is write > intensive, such as a database server. Raid5 is a cost compromise that is a > little of everything, if you want protection and speed at the same time, > you should use raid1 (and possible raid0 the raid1:s). > > I learnt this the hard way running a nntp (news) server. > > -- > Mikael Abrahamsson email: swmike@xxxxxxxxx ------- End of Original Message ------- - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
