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Message Posted: Thu, 10 Oct 2002 @ 06:07:20 GMT
Packdisk does not need to be run on spool. Spool is built in nice 64K/128K blocks layed down in a row so there is no fragmentation and therefore nothing to pack.
There is a new command in ferret for 4.1 called
It allows you to pretend you are running a packdisk and it will estimate how many cylinders would be reclaimed from each table after the packdisk was done if you actually did the packdisk.
if you want to simulate a
packdisk fsp = 15
you would issue
showfsp -d 15
I recommend running it on a single AMP
scope vproc 0
since amps are probably fragmented equally. If you want you could pick a couple amps
scope vproc ( 0, 5, 10, 15, 20 , 25, 30 )
and compare the results. here is a sample result.
1:vproc 15 (000F) response 1: 1:There are 2 tables larger than 45 cylinders on amp 15 1: 1:Database Table fsp Recoverable Current 1:Name Name % Cylinders Cylinders 1:----------- ------------------------- ----- ----------- ------- 1:Crashdumps Crash_20010223_155740_09 35 11 47 1:V2R3RB TABLE01 32 19 98
what this says is that if I was to pack just these 2 tables I could recover 30 of the 145 cylinders these 2 tables occupy and packdisk would only have to scan 145 cylinders to complete rather than having to scan the whole system.
Using showfsp and scope table allows packdisk to be a lot more efficient, in this example we could recovering 20% of the cylinders packdisk scans.
Here is how you use the list to run a "PACK TABLE" on just the specified tables.
scope table "Crashdumps.Crash_20010223_155740_09" 0
scope table "V2R3RB.TABLE01" 0
Now granted your tables would be much bigger than my example tables here, but the concept is the same.
If recoverable Cylinders is negative it means that this table would actually be UNPACKED to the desired fsp if you ran a full system packdisk and therefore occupy that many more cylinders once the packdisk completes.
Showfsp has other options which allow you to tailor the list to your preferences like.
only examine tables > 200 cylinders ( -c 200 ) only display tables where we can reclaim more than 20 cylinders. ( -r 20 ) -a Show all tables bigger than -c
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