LTFS on HP Ultrium 3000 SAS - transfer speed poor with large directories with multiple files (335 Views)
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Occasional Visitor
thomasu
Posts: 1
Registered: ‎02-04-2013
Message 1 of 3 (335 Views)

LTFS on HP Ultrium 3000 SAS - transfer speed poor with large directories with multiple files

Hello LTO5 LTFS users & HP

 

We have been using HP's LTFS software and drivers on our Ultrium 3000 and with the Dec 7 Storeopen release of code things got much more stable.  However, when copying folders that contain a large number of files, in our case .tif or .dpx file types (image files), and often in to the 10s of thousands, the transfer slows and slows.  It starts at a the full 140mb/sec for the first 1000, then slowly drops and drops, and eventually its 50mb a minute when its 20,000-30,000! It only resumes its speed when a new directory is created.

Has anyone else come across this?  We are in a Professional Broadcast environment so each file is 6-10mb, and adopts the naming convention: 000001.dpx, 000002.dpx

 

Many thanks

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Occasional Visitor
DarkAlman
Posts: 1
Registered: ‎05-14-2013
Message 2 of 3 (270 Views)

Re: LTFS on HP Ultrium 3000 SAS - transfer speed poor with large directories with multiple files

We are having similar issue with an Ultrium 5 tape drive.

 

Anytime we try to copy large volumes of files it slows to a crawl.

 


It looks like HP's implementation of LTFS has no or little buffering, so everytime it writes a file it has to rewind the tape, write to the index and then spool forward again.

Hopefully they will fix it soon, it's pretty useless in this form unless I zip my backups first.

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Occasional Visitor
gomes_thiago
Posts: 1
Registered: ‎07-18-2013
Message 3 of 3 (214 Views)

Re: LTFS on HP Ultrium 3000 SAS - transfer speed poor with large directories with multiple files

Some answer?

 

Our customer use LTFS in MAC with LTO 5, for write of files until 50GB the transfer rate is 140MB/s, if the file is bigger go down slowly for 10MB/s

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