Re: The 2GB chunk size limit and Sparc storage arrays
On 18 Jan 1996, Mike Reed - Radiix wrote: > Does anyone know if Informix will be removing the 2GB > chunk size limit anytime soon? > > I (think) I've come across an irritation while using the > Sparc storage array with Online Disk Suite 4.0. Our Sun SE > told me (and showed me) that the maximum number of logical > names that can be used on a system is 127 (the /dev/md/rdsk > names). If this is true, then I can only have 42 - 2GB > partitions on a Sun because it takes at least 3 of the > logical names to make a mirrored volume. If there wasn't > a 2GB limit per chunk in Informix, this would probably not > be a problem, although I have to wonder what Sun was thinking > when they imposed such a limit. I hope our Sun SE was wrong > and this is not true. > > Anyone have any insight? > > Michael Reed, Radiix Inc. > mreed@radiix.com > > Mike, In addition, with the 2GB chunk size, you can only read into the disk a distance of 2GB. For example, if you have a 4GB disk and offset the chunk by 1GB, you will not be able to fully use that chunk. The chunk will say it is 2GB, but when writing to the locations greater than 2GB from the start of the disk, it may actually over-write data at the beginning of the chunk. I have run into this in the past and it did destroy data. We are using the Sun Storage Array on a Sun 2000E and using the disks as raw devices and building chunks and dbspaces from there. We are not using the Online Disk Suite. If ODS does give you major performance increases, then I need to check into it to see the feasability of using ODS. Regards, +----------------------------------------------------------------------------+ | | | | . . | | | ... ... | Darin Melin | | ..... ..... | Software Engineer, DBA | | .. ... .. | Business Systems Integration Group | | . . . | Semiconductor Products Sector - LATG | | | 2100 E. Elliot Road, MD EL557 | | | Tempe, AZ 85284 | | Motorola, Inc. | rp29560@email.sps.mot.com Phone:(602) 413-5756 | | | melin@bsi.sps.mot.com FAX: (602) 413-5566 | | | Director - Arizona Informix Users Group | +----------------------------------------------------------------------------+ | 'connectionLESS IS MORE' -- Data Broker | +----------------------------------------------------------------------------+