Subject | Re: [firebird-support] Re: Fill ratio when doing a restore |
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Author | Ann W. Harrison |
Post date | 2006-10-06T16:18:51Z |
Adam wrote:
fixed percentage of space that's reserved. For each primary record
stored on a page, space is reserved for one fragmented record header.
If your table is wide, so few primary records fit on a page, little
space is reserved. If your table is narrow, lots of primary records
fit on a page, so more space is reserved.
what fraction of a fragmented record header should be reserved
on each page per primary record, or even which fraction should
be reserved for each table. Then we could explain to everyone
who had a performance problem that they needed to tune the fill
factor for each table, even though the fill factor really only
affects a newly loaded database.
Regards,
Ann
>Err, if you'd read the previous message, you'd know that it's not a
> A quick question on this one, is there a reason that it is a 100%/60%
> toggle rather than allowing the user to set the percentage?
fixed percentage of space that's reserved. For each primary record
stored on a page, space is reserved for one fragmented record header.
If your table is wide, so few primary records fit on a page, little
space is reserved. If your table is narrow, lots of primary records
fit on a page, so more space is reserved.
>I suppose we could offer an option that the user to determine
what fraction of a fragmented record header should be reserved
on each page per primary record, or even which fraction should
be reserved for each table. Then we could explain to everyone
who had a performance problem that they needed to tune the fill
factor for each table, even though the fill factor really only
affects a newly loaded database.
Regards,
Ann