Hi, Sqlite uses pread and the performance with ramdisk and disk is the same on Linux SuSE9.
regards ragha ****************************************************************************************** This email and its attachments contain confidential information from HUAWEI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it! ***************************************************************************************** ----- Original Message ----- From: Lee Crain <[EMAIL PROTECTED]> Date: Wednesday, August 22, 2007 3:31 am Subject: RE: [sqlite] A Question About Creating and Accessing a SQLite Database in a RAM Drive > Rich, > > We're going to delete and rewrite ~109,369 records in 5 tables > every week. > > > Hard drives are a minimum of 10,000 times slower than RAM. I'll > let you > know if this process is not a lot faster than writing the records, > individually, to a hard drive. > > Lee Crain > > _________________________________________________ > > > -----Original Message----- > From: Rich Shepard [mailto:[EMAIL PROTECTED] > Sent: Tuesday, August 21, 2007 11:15 AM > To: sqlite-users@sqlite.org > Subject: RE: [sqlite] A Question About Creating and Accessing a SQLite > Database in a RAM Drive > > On Tue, 21 Aug 2007, Lee Crain wrote: > > > The approach I planned was a little different than what you > proposed. > That's fine, Lee. > > > This technique for performing database updates offline and then > updating> the original database via a file copy operation has > worked very well on > > hard drives. I am only considering using the RAM drive to > improve the > > speed of the database updates. > > This was common in the early 1980s when drives and other > hardware were > slow. I've not seen a situation any time recently when this was > necessarywith modern hardware and fast memory. When I was > capturing real-time data > (lat/lon from the GPS receiver and depth from the sonar), I'd > write both > to > memory buffers, then write to disk on a regular basis. This let me use > slower hardware (compared to the data flow) while writing to disk in > chunks > and ensuring that no data were lost. > > I'm confident that you can tune your database for speed in > other ways, > but > -- of course -- it's your choice. > > Good luck with it, > > Rich > > -- > Richard B. Shepard, Ph.D. | The Environmental > PermittingApplied Ecosystem Services, Inc. | > Accelerator(TM)<http://www.appl-ecosys.com> Voice: 503-667- > 4517 Fax: > 503-667-8863 > > ------------------------------------------------------------------- > ------- > --- > To unsubscribe, send email to [EMAIL PROTECTED] > ------------------------------------------------------------------- > ------- > --- > > > > ------------------------------------------------------------------- > ---------- > To unsubscribe, send email to [EMAIL PROTECTED] > ------------------------------------------------------------------- > ---------- > > ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
