optimizing informix IDS at a raw device level

Hi, I'm about to migrate an informix database from a server to another SUN Spark E4500 Solaris server. The new server will take place on a 2Tb SCSI array. I want to make a big stripe between some disks. Then, final raw devices will be created with vxva. While building my stripe, I would like to know what is the average write size of informix to be able to optimize stripe block size the best I can. Informix Support said : 2K (size of a page). Question : -Is this right ? -Why do I see something else when I truss some "oninit" process : truss -t read,write,lseek -p 422 write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 write(61, "\\00E\\0\\0041B 0 3 0 0 2 7".., 1088) = 1088 write(61, "\\00E\\0\\0\\0D2 0 3 0 0 2 0".., 246) = 246 write(61, "\\00E\\0\\00504 0 3 0 0 2 0".., 1320) = 1320 write(61, "\\00E\\0\\0029C 0 3 0 0 2 0".., 702) = 702 write(61, "\\00E\\0\\002 7 0 3 0 0 0 9".., 602) = 602 write(61, "\\00F\\0\\0\\0\\0\\0\\005 jB103".., 30) = 30 write(59, "\\00E\\0\\0\\0 V 0 3 0 R V _".., 94) = 94 write(58, "\\00E\\0\\00504 0 3 0 0 2 0".., 4096) = 4096 write(58, " 0 0 0 0 080\\0\\0\\0\\0\\0\\0".., 4096) = 4096 write(58, " 0 0 0 0 0 0 0 0 ".., 4096) = 4096 write(58, " H P".., 4096) = 4096 write(58, " 0 0 0 ".., 2968) = 2968 write(61, "\\00E\\0\\0\\0 Y 0 3 0 0 2 0".., 126) = 126 write(61, "\\00F\\0\\0\\0\\0\\0\\011 aEB1D".., 30) = 30 write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 write(61, "\\00F\\0\\0\\0\\0\\0\\0 a 3D904".., 30) = 30 write(58, "\\00E\\0\\00504 0 3 0 0 2 0".., 4096) = 4096 write(58, " 0 0 0 0 080\\0\\0\\0\\0\\0\\0".., 4096) = 4096 write(58, " 0 0 0 0 0 0 0 0 ".., 4096) = 4096 write(58, " H P".., 4096) = 4096 write(58, " 0 0 0 ".., 2968) = 2968 write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 file descriptors 58-61 refers to raw devices, as seen in lsof output... -- _______________________________________________ Sebastien THOMAS none networks System Engineer freesbee geo:153, rue Saint-Denis, 75002 Paris, France vox:+33 1 45 08 23 10 - fax:+33 1 45 08 25 29 mailto:sebastien.thomas@none.net

The best stripe blobk size for Informix is between 8 and 16K. I will STRONGLY recommend that you configure for RAID10 for maximum performance and safety. Art S. Kagel Sebastien THOMAS wrote: > > Hi, > > I'm about to migrate an informix database from a server to another > SUN Spark E4500 Solaris server. > The new server will take place on a 2Tb SCSI array. I want to make a big > stripe between some disks. > Then, final raw devices will be created with vxva. > While building my stripe, I would like to know what is the average write > size of informix to be able to optimize stripe block size the best I > can. > Informix Support said : 2K (size of a page). > > Question : > -Is this right ? > -Why do I see something else when I truss some "oninit" process : > > truss -t read,write,lseek -p 422 > > write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 > write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 > write(61, "\\00E\\0\\0041B 0 3 0 0 2 7".., 1088) = 1088 > write(61, "\\00E\\0\\0\\0D2 0 3 0 0 2 0".., 246) = 246 > write(61, "\\00E\\0\\00504 0 3 0 0 2 0".., 1320) = 1320 > write(61, "\\00E\\0\\0029C 0 3 0 0 2 0".., 702) = 702 > write(61, "\\00E\\0\\002 7 0 3 0 0 0 9".., 602) = 602 > write(61, "\\00F\\0\\0\\0\\0\\0\\005 jB103".., 30) = 30 > write(59, "\\00E\\0\\0\\0 V 0 3 0 R V _".., 94) = 94 > write(58, "\\00E\\0\\00504 0 3 0 0 2 0".., 4096) = 4096 > write(58, " 0 0 0 0 080\\0\\0\\0\\0\\0\\0".., 4096) = 4096 > write(58, " 0 0 0 0 0 0 0 0 ".., 4096) = 4096 > write(58, " H P".., 4096) = 4096 > write(58, " 0 0 0 ".., 2968) = 2968 > write(61, "\\00E\\0\\0\\0 Y 0 3 0 0 2 0".., 126) = 126 > write(61, "\\00F\\0\\0\\0\\0\\0\\011 aEB1D".., 30) = 30 > write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 > write(61, "\\00F\\0\\0\\0\\0\\0\\0 a 3D904".., 30) = 30 > write(58, "\\00E\\0\\00504 0 3 0 0 2 0".., 4096) = 4096 > write(58, " 0 0 0 0 080\\0\\0\\0\\0\\0\\0".., 4096) = 4096 > write(58, " 0 0 0 0 0 0 0 0 ".., 4096) = 4096 > write(58, " H P".., 4096) = 4096 > write(58, " 0 0 0 ".., 2968) = 2968 > write(61, "\\00F\\0\\0\\0\\0\\0\\0\\0\\0\\0\\0".., 30) = 30 > > file descriptors 58-61 refers to raw devices, as seen in lsof output... > > -- > _______________________________________________ > Sebastien THOMAS none networks > System Engineer freesbee > > geo:153, rue Saint-Denis, 75002 Paris, France > vox:+33 1 45 08 23 10 - fax:+33 1 45 08 25 29 > mailto:sebastien.thomas@none.net