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After upgrading to Lion (10.7.1) a while ago I'm currently faced with a very poor performance of my system. It's a 2.2 GHz Core2Duo with 4 GB RAM and a 500GB HD. E.g. the JBoss6 AS needs about 5 minutes to start (compared to 1 minute before facing this problems), or after starting Safari and loading a page it's freezed about 5-10 seconds until the Flash animations are available.

I tried the XBench test and wondering about the Disk Tests [4K blocks, 256K blocks]:

Sequential Write: 49  MB/s, 12 MB/s
Sequential Read:  0.8 MB/s, 10 MB/s
Random Write:  0.8 MB/s, 9 MB/s
Random Read:   0.1 MB/s, 7 MB/s

The throughput during read times seem to be extremely low. Can this be a problem with the HDD? (SMART status is verified). iDefrag show fragmentations between 0.2% to 0.4% of volume content, but about 60% (catalog) to 70% (free space) of the volume directory.

Note: The Thread Test of XBench seems never to complete, the last entry is

Computation:  187.19 4.79 Mops/sec, 4 threads  
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is the Spotlight running and re-indexing? – kukoo Sep 21 '11 at 15:42
Unrelated: You shouldn't need to defrag HFS volumes. There's a great (though somewhat dated) writeup on this here: – Harv Sep 21 '11 at 18:30
@kukoo Spotlight is no re-indexing – Thor Sep 21 '11 at 19:32
@Harv I know ... but with this kind of problems you begin to think about such stuff ;-) – Thor Sep 21 '11 at 19:32

Ok, I bought a new Harddisk (Samsung 640GB) and cloned the old HD with SuperDuper. After Spotlight has re-indexed the drive I have the following benchmarks:

Sequential Write: 60  MB/s, 25 MB/s
Sequential Read:  17 MB/s, 69 MB/s
Random Write:  1.5 MB/s, 24 MB/s
Random Read:   0.5 MB/s, 19 MB/s

I don't know if the HD or it's controller is damaged, but now the performance of my system is ok again!

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