Talk:Hardware compression: Difference between revisions
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--[[User:Maximd|maximd]] 05:02, 12 March 2009 (PDT) | --[[User:Maximd|maximd]] 05:02, 12 March 2009 (PDT) | ||
Best is to run '''amtapetype -c''' with a scratch tape inserted (it will be erased). It detects hw compression without trusting any settings, but by measuring tape write speed difference, a direct result of the fact that very compressable input data results in much less bits to write to tape with hw compression on, and thus a significant larger throughput in that case. | |||
(See man page for more details). | |||
--[[User:Paul.bijnens|Paul.bijnens]] 05:49, 12 March 2009 (PDT) | |||
Latest revision as of 12:49, 12 March 2009
Shouldn't the Linux example mt -f /dev/nst0 datcompression 0 actually be mt -f /dev/nst0 defcompression 0?
Paddy 13:24, 5 January 2007 (PST) Yes. you are correct. I will fix it.
Verifying hardware compression status
Is there any way to verify that the hardware compression is actually ON or OFF?
--maximd 05:02, 12 March 2009 (PDT)
Best is to run amtapetype -c with a scratch tape inserted (it will be erased). It detects hw compression without trusting any settings, but by measuring tape write speed difference, a direct result of the fact that very compressable input data results in much less bits to write to tape with hw compression on, and thus a significant larger throughput in that case. (See man page for more details).
--Paul.bijnens 05:49, 12 March 2009 (PDT)