I have successfully removed directories from file device classes a number of times. The sequence of events was as follows: 1.Remove the directory from the list in the device class definition to prevent allocation of new scratch volumes on the directory. 2.List filling volumes on the directory and make them read only, preventing appends to existing volumes on the directory. 3.Run "move data" commands to relocate the contents of volumes to other directories. 4.Wait for database backups and pending volumes to age off.
The Linux administrator thought step 3 would have better overall throughput with multiple streams of "move data" commands. I used the "-P" option of "xargs" to manage the multiple streams. Thomas Denier, Thomas Jefferson University -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Rhodes, Richard L. Sent: Tuesday, February 14, 2017 08:35 To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] Multiple NFS mounts to same DataDomain Arnaud's discussion on the another thread is SO interesting (Availability for Spectrum Protect 8.1 server software for Linux on power system). It got me thinking of our problems . . . > NFS, whose performance is not that good on AIX systems Agreed!!! After getting DataDomain system and using NFS we were/are VERY unhappy with the NFS performance. Our Unix admins worked with IBM/AIX support, and finally got an admission that the problem is AIX/NFS using a single TCP socket for all writes. The workaround was to use multiple mount point to the same NFS share and spread writes (somehow) across them. He did this and got higher throughput. So now I'm wondering if we could use multiple NFS mounts to the same DD for our file device pools. aix: /DD/tsm1/mnt1 dd: /data/col1/tsm1/mnt1 /DD/tsm1/mnt2 /data/col1/tsm1/mnt2 /DD/tsm1/mnt3 /data/col1/tsm1/mnt2 Then use multiple dir's for the file device devclass: define devclass DDFILEDEV devtype=file dir=/DD/tsm1/mnt1,/DD/tsm1/mnt2,/DD/tsm1/mnt3 According to the link to dsmISI again, TSM will roughly balance across the multiple mount points, hopefully giving better write throughput. I've been VERY reluctant to try this since it appears once you add a dir to a file device devclass, it's there forever! I'm curious if anyone is doing this. Rick The information contained in this transmission contains privileged and confidential information. It is intended only for the use of the person named above. If you are not the intended recipient, you are hereby notified that any review, dissemination, distribution or duplication of this communication is strictly prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message. CAUTION: Intended recipients should NOT use email communication for emergent or urgent health care matters.
