Re: Configuring raw devices

From: Elena Korol <ekorol@styleclick.com> > >I have read some of ongoing discussions on comp.databases.informix about >configuring raw disk space on a storage array. >Here is the situation I have with a new Sparc server Solaris 8 and RAID 10 >created by Disk Suite 4.2 (software RAID on A5000). > >Currently we have formatted 10 9Gb drives in a stripe/submirror with 10 >other drives mirrored. >So total space on our software RAID 10 is under 90Gb. >The RAID device right now looks like one 90Gb partition. All of it is >dedicated to for the data storage. Operating and Informix file systems are >on a separate SCSI drive. > >I understand that to use raw dbspaces, informix would like to have 2Gb >partitions. >What will be the most efficient way to create an Informix instance on a raw >dbspace larger than 2GB? >Since we are using software RAID, it looks like a big overhead to >repartition each array drive into four 2Gb partitions with 1GB partition >leftover. >Also each drive has to be sliced and mirrored... > >Company does not own Veritas Volume Manager, so we are stuck with Solstice >DiskSuite. > >Should we forget about raw devices and go with the cooked file system? NO!!!! Despite what anyone may say about modern file systems being just as fast, you can expect a performance hit of 15-35% on performance, plus unless you set your kernel up carefully, the OS cache can easily cause swapping as you double cache the data. ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com