Direct I/O
What is better 1) Should we enable informix Direct I/O only? 2) Should we enable direct I/O of UFS ? as # mount -o forcedirectio /dev/dsk/c0t1d0s2 /db1 3) Should we enable both Direct I/O of Informix and UFS Please suggest me
KHURRAM SHAHZAD wrote: > What is better > > 1) Should we enable informix Direct I/O only? > 2) Should we enable direct I/O of UFS ? > > as > > # mount -o forcedirectio /dev/dsk/c0t1d0s2 /db1 > > 3) Should we enable both Direct I/O of Informix and UFS > > Please suggest me Use raw, for fuck's sake! -- Cheers, Obnoxio The Clown http://obotheclown.blogspot.com I will now proceed to pleasure myself with this fish. -- This message has been scanned for viruses and dangerous content by OpenProtect(http://www.openprotect.com), and is believed to be clean.
RAW first choice! DIRECTIO under Informix control second choice (just because I don't know if anyone has made any substantial tests of using a filesystem that's been mounted with DIRECTIO turned on for all writes with Informix). Art Art S. Kagel Advanced DataTools (www.advancedatatools.com) IIUG Board of Directors (art@iiug.org) Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Fri, Jul 30, 2010 at 7:24 AM, KHURRAM SHAHZAD <kshahzad02@i2cinc.com>wrote: > What is better > > 1) Should we enable informix Direct I/O only? > 2) Should we enable direct I/O of UFS ? > > as > > # mount -o forcedirectio /dev/dsk/c0t1d0s2 /db1 > > 3) Should we enable both Direct I/O of Informix and UFS > > Please suggest me > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --001485f44c029fb60e048c9ad7d5
good day all, When You say RAW I'd guess that you mean RAW Informix device so DBSPACES device pointing to /dev/sdc instead of (cooked) file on the linux filesystem. Have anybody tested the VMWare Raw Device Mapping (RDM) devices attached to Virtual Machine (Linux) with Informix inside? In both cases the disk is attached to Virtual Machine in the same way but with normal disks it's just a .vmdk file on the LUN and with RDM it's direct access to the LUN. Did anybody play around with that? - the performance tests and problems
Regardless of what anyone says YMMV, you really should test it yourself. Art Art S. Kagel Advanced DataTools (www.advancedatatools.com) IIUG Board of Directors (art@iiug.org) Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Fri, Jul 30, 2010 at 11:17 AM, WALDEMAR ZNOINSKI <waldek@znoinski.pl>wrote: > good day all, > When You say RAW I'd guess that you mean RAW Informix device so DBSPACES > device pointing to /dev/sdc instead of (cooked) file on the linux > filesystem. > Have anybody tested the VMWare Raw Device Mapping (RDM) devices attached to > Virtual Machine (Linux) with Informix inside? In both cases the disk is > attached to Virtual Machine in the same way but with normal disks it's just > a > ..vmdk file on the LUN and with RDM it's direct access to the LUN. Did > anybody > play around with that? - the performance tests and problems > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --0016e65a01f6484627048c9d82e9