Not quite !! 99.999% or 'the five nines' sounds much better ;-) With 64-bit computing we can address SGA sizes in the order of few TBs (if not PBs), why worry about disk I/Os except for two occasions ;-)) Then the 'five nines' can be 'nine nines'. Wow!! That sounds even better.. much much better ;-)))
- Kirti -----Original Message----- Sent: Wednesday, March 20, 2002 5:48 AM To: Multiple recipients of list ORACLE-L Cary Milsap from hotsos has much data to confirm an approximate 1:100 ratio between LIO time and PIO time. Can we therefore conclude, that the buffer cache hit ratio should be 99%? :-) Rgds, Bj�rn. On Wednesday 20 March 2002 10:48, Connor McDonald wrote: > Some rudimentary testing on a laptop here (500Mhz, > 512M RAM, typical single disk) > > a) visiting a single block via 4,000,000 logical IO's > got me approx 35000 gets/sec > > b) repeated full table scans similar system got me > approx 350 phys reads/sec > > After this extensive, thorough and exhaustive > exercise, I can definitely say that memory access > versus disk access (as it pertains to Oracle) is 100 > times faster on this machine in single user mode > > I think we can generalise this to be the rule for all > servers under all conditions :-) > > Connor > > -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Deshpande, Kirti INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
