puzzling SAS I/O question
in [SAS]
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From: Proc Me on 1 Feb 2010 17:37 Michael, Thank you for your kind words. I'm writing this intro after the content, so I can see that this post may be of more interest to those beginning their SAS journeys. >I would be _VERY_ interested if any 'L-ers get meaningful reductions in >I/O's on SAS 9.2 (TS2M0 or TS2M2) under Windows XP. Not on the pretty >plaything data sets generated with multiple DO loops for proof-of-concept >SAS-L postings, but on real-life large-sized data sets. Inquiring minds >want to know! I've done some testing and the results are better, but we're running 9.2TS2M2 against a Win2k3 Enterprise Edition server, rather than XP, with data on SAN, so the results may not be comparable. I'd be happy to share what we have if I can dig out, or regenerate, some meaningful evidence. One thing that definitely paid off is monitoring resource usage, if you have memory you're not using, use it. You can do this by increasing its usage through the memory buffer product (bufsize*bufno). This has made a difference, up to a ceiling of 2GB - now explained by the paper from TB and MC. Setting the bufsize small also appears to help with sorting data - intuitively this makes a certain sort of sense: its easier to get to the bits you want when you've got lots of small chunks. >BTW, both Tony Brown and Margaret Crevar have written other stellar >papers; I'm a big fan of both of them... but let's just keep that between >the two of us. I agree: stars in the SAS firmament! I'll pop over to lexjansen.com to make sure I've not missed anything, and would welcome any pointers. When we relocated our server recently we did it by commissioning a new machine. I wrote the spec based on their best practices, and I'm confident that we've got a better machine for it. Our IS department really responded when they saw "business users" who cared passionately and who had answers for many of the design questions they had - the post-project debrief was a bit of a love-in. Proc Me |