On Fri, Apr 3, 2015 at 1:40 AM, Octavi Fors <octavi@xxxxxxxxxxxx> wrote: > Hi David, John et al., <snip> > Oops, sorry yes I think I may "miss-spoke" when explaining my second reason > why not choosing eSATA. > My situation is the following: > > -Two computers (C1 & C2) and NAS (with no eSATA I/O) on the same LAN. > -C1 acquires images from a telescope and periodically stores them via NFS in > the NAS (no database involved here, just in the ext4 filesystem). > -C2 is a 12 xeon core-class server designed to analyze the stored images in > the NAS, and compute astrometry & photometry measurements (catalogs & light > curves) for every star & image. These measurements are inserted in the > catalogs database inside the NAS. > > Therefore there's only *one* computer (C2) which will run postgresql server > with the tablespace onNAS. > > So does this approach sound like feasible if the NFS parameters are set > properly? OK, it is very understandable why the images are on the NAS. It is the easiest way to share them. I guess you want the DB on the NAS simply because you don't have sufficient disk space on the disks connected to C2. > <snip> > Could you confirm that > nas_ip:/volume1/data /home/ofors/Documents/nas nfs noac,sync > would be good options for /etc/fstab? > > Any additional NFS parameter? Have you done a web search on "NFS Performance"? I got some good hits with Google. http://www.tldp.org/HOWTO/NFS-HOWTO/performance.html (a bit old, I've been told) http://www.cyberciti.biz/faq/linux-unix-tuning-nfs-server-client-performance/ Mentions "noatime" and "nodiratime" to not update the last access date/time on files & directories, saving bandwidth. A good explanation of the NFS mount options, IMO, are on this site: http://www.dbaexpert.com/blog/nfs-options-for-performance/ Some interesting "speed test" code: https://github.com/sabujp/nfsSpeedTest > <snip> > Thanks a lot in advance, > -- > Octavi Fors -- If you sent twitter messages while exploring, are you on a textpedition? He's about as useful as a wax frying pan. 10 to the 12th power microphones = 1 Megaphone Maranatha! <>< John McKown -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
