On Fri, May 16, 2003 at 01:25:18PM -0400, Gene Heskett wrote:
> 
> One other item that should be considered if taping as soon as the 
> chunk is available is done, and that is the relative speed of the 
> compressor (usually gzip) compared to the i/o rate of the drive.  
> I'd certainly want to avoid the situation where the drive was 
> starved for data and quits streaming.  With my relatively slow DDS2 
> drive, I doubt it would be a problem, but can "gzip best" spit out 
> chunks at 20+mb/sec for some of the latest big drives?  "No way 
> josea" would be my first response.  The hardware hasn't gotten that 
> fast *yet*.

If I recall, there was to be a "chunksize" param.  If this were set
too small "shoe shining" could be a problem (ie, stream, stop, backup,
resync, start streaming again).

I'd try to avoid it by setting chunksize large.  Say 1GB for my 12 GB
tapes.  I assume that small dumps would not be padded out to the chunksize.
That would let a lot of my level 0's, and nearly all my incrementals
tape without chunking.  Things that were "chunked" would still stream
for a high percentage of the tape.
-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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