On Sun, May 22, 2011 at 2:06 PM, Keith Roberts <keith at karsites.net> wrote: > On Sun, 22 May 2011, yonatan pingle wrote: > >> To: CentOS mailing list <centos at centos.org> >> From: yonatan pingle <yonatan.pingle at gmail.com> >> Subject: Re: [CentOS] SSD for Centos SWAP /tmp & /var/ partition >> >> On Sun, May 22, 2011 at 10:57 AM, Steven Crothers >> <steven.crothers at gmail.com> wrote: >>>> >>>> I was running on 3gbps sata bus, and the performance was great, it >>>> just dies in one big crash without giving any clues about it. >>> >>> If only SSD's were a viable solution for long-term storage, we could >>> theoretically increase our virtualization many times over. It's to bad >>> the technology hasn't come far enough to be used that way though >>> without costing an arm and leg. > > But it's going in the right direction now. > >>> -- >>> Steven Crothers >>> steven.crothers at gmail.com > > >> the only way to go with SSD is RAID due to these reasons. >> it's unlikely that two disks will die at the same time, so it's >> possible to use and enjoy them , >> but don't forget to have a fresh backup and a raid array. ( that >> should be done also with an ordinary disk array anyways ). > > That's EXACTLY what I was thinking. Two 40GB SSD drives in a RAID array > would not cost much at all. Move all the disk intensive stuff to that. I > only have two root partitions of 20GB each for my main install - everything > else is on other partitions on 2 x 500GB E-IDE drives. So putting the root > partion on a small SSD (possibly RAIDed) is another option. Like most new > electronics components, as time passes the mass production cost fall > dramatically, and the technology improves. Look at the way HDD technology > continues to advance. > > Maybe in 5 years time the cost of SSD's will be alot cheaper? Possibly in > another 15 years time HDD's with moving parts will be consigned to history > and science museums? I'm watching this technology very closely, and I'm very > tempted to buy a small 40GB SSD like OWC's. > > They keep performing at optimal speed according to the specs for that drive. > > The OWC SSD's are supposed to have a MTTF of 2 million hours, PLUS they do > not degrade over time. So if an OWC keeps going until MTTF, that's 24 x 365 > = 8760 HPY. 2000000 / 8760 = 228.31 years MTTF ? > > So why does it only have a 3 year warranty? - LOL > > For me anything on SWAP has to be better than a s/h drive thats had almost a > years running time according to the SMART data on the drive: > > 9 Power_On_Hours 0x0032 090 090 000 > Old_age Always - 7913 > > 329 days running time already - let's see how long this one lasts before it > kicks the bucket. > > Kind Regards, > > Keith Roberts > > ----------------------------------------------------------------- > Websites: > http://www.karsites.net > http://www.php-debuggers.net > http://www.raised-from-the-dead.org.uk > > All email addresses are challenge-response protected with > TMDA [http://tmda.net] > ----------------------------------------------------------------- > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > > I hardly swap to disk these days , and after the bad experience with ssd as swap only ... i would stick to RAM & sata. RAM is so cheap , just get extra ram , and use PAE if 32bit (?) adjust vm.swappiness ( sysctl ) to a lower value then 60 ( default ) , and you will be fine swapping on sata drives if and when needed. if you are afraid of memory fragmentation , don't be .. in most cases you will be rebooting the server when a new kernel update will come out as it is.... the main question is , which kind of applications are you planning to run on your machine, and what is your actual hardware *needs*, that only you can tell. also, for /tmp , you might like the idea of a ramdisk ( or tmpfs ) , it is a great way to speed up things without breaking the piggy bank. this is what i use in /etc/fstab for my home desktop as /tmp : /tmpfs /tmp tmpfs size=512M,nr_inodes=5k,noatime,nodiratime,noexec 0 0 does the job well. anyways - if it's for home usage Don't think twice get an SSD . -- Best Regards, Yonatan Pingle RHCT | RHCSA | CCNA1