Kbase P26191: Can you use 8k database blocksize on Linux?
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
5/30/2003 |
|
Status: Unverified
GOAL:
Can you use 8k database blocksize on Linux?
FACT(s) (Environment):
Linux Intel
FIX:
One should always use a database block size that matches the filesystem's
page size or block size (depending on the type of filesystem). Using a
smaller database block size gives bad performance. Using a larger
database block size decreases reliability slightly. It introduces a small
possibility that a database block could be partially written to disk if a
complete system crash (say a power failure) occurs at the right moment. In
most cases, database writes will be atomic, but not always. Database writes
will usually be performed as a single disk write by the os even though two
filesystem pages may be involved. But sometimes a database block could be
split across a track boundary or something and the write not be atomic.
None of this is unique to Linux.
None of the filesystems on Linux currently allow block sizes larger than
4K. This is because of the virtual memory architecture of the Linux 2.4
(and earlier) kernel.