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From:alec.cawley Date:January 17 2002 3:00pm
Subject:Re: Memory
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> I suggest setting record_buffer to 1 MB. Disk reads in blocks of 1 MB are
> probably as fast as in blocks of 10 MB.

I agree

A typical modern disk has an average access time of 5.5 msec and a transfer
rate of 40 Mbyte/sec.
This means that the two are the same for a disk transfer of about 200kbyte.
Therefore,
tranfers significantly smaller than 200kb will be wasteful because of too
many seeks, whereas
transfers more than a few times this will be wasteful (unless all the data
is used) because of
time spent getting data which is never used. For a disk of this type (good
scsi 10,000 rpm), I
would have thoght a transfer size of 0.5-1.0 megabyte would be a good
target. If the disk
has lower acces tume (e.g. 15,000 rpm) reduce the transfer size. If the
disk is externally
raid-ed, probably increase the transfer size.

     Alec Cawley (who uses disks for video servers)

SQL database



Thread
MemoryJohn Kemp17 Jan
  • Re: MemoryJeremy Zawodny17 Jan
Re: MemoryHeikki Tuuri17 Jan
  • Re: MemoryJohn Kemp17 Jan
  • Re: MemoryJeremy Zawodny17 Jan
    • Re: MemoryDan Nelson18 Jan
      • Re: MemoryJeremy Zawodny18 Jan
Re: Memoryalec.cawley17 Jan
Re: MemoryHeikki Tuuri17 Jan