ML 10.8.2 causes excessive HDD access when idle (once/sec)

[bluesky]

My hackintosh seems to query the HDD about once per second for reasons I cannot understand. Example, I boot the machine fresh and just sit on the desktop with nothing running. The HDD light flashes about once/sec. Any ideas how can I figure out what is doing this and stop it?

Link to youtube video showing this in action.

 

[Macblack4]

Probably Spotlight indexing the hard drive, or OSX defragging the hard drive. Completely normal activities. FYI Apple has been building the Macintosh since 1984, and no Mac ever had a hard drive access light.

 

[rlf156]

1. See what processes are running on your computer and which ones are using the most CPU time. They might be the ones accessing the disk. Open Activity Monitor found in the Applications -> Utilities folder. Click on the "% CPU" column header to sort by "% CPU". Click until the largest CPU activity is first.

2. Monitor the actual disk usage. Open Terminal found in the Applications -> Utilities folder.

Type: sudo fs_usage -w -f filesys
(give your password - the cursor will not move - there will be no feedback)

Watch the right column for the process or app that is accessing the disk. If a second line appears, that is the file involved in the disk access.

To stop the monitor, press Control-C.

 

[bluesky]

Thank you, very useful command. Here is the output:

$ sudo fs_usage -w -f filesys
16:49:04.843585  getattrlist                                                                                                                                                                                                  0.000014   Finder.80139
16:49:04.938629  getattrlist                            /Volumes/Data                                                                                                                                                         0.000013   Finder.80139
16:49:17.830456    WrData[SP]      D=0x0000c560  B=0x200        /dev/disk0s3                                                                                                                                                  0.000237 W kernel_task.80178
16:49:17.859020  IOCTL             <DKIOCSYNCHRONIZECACHE>      /dev/disk0s3                                                                                                                                                  0.028559 W kernel_task.80178
16:49:17.859436    WrData[ST]      D=0x0002b11d  B=0xa200       /dev/disk0s3                                                                                                                                                  0.000402 W launchd.217
16:49:17.867928  IOCTL             <DKIOCSYNCHRONIZECACHE>      /dev/disk0s3                                                                                                                                                  0.008467 W launchd.217
16:49:17.868127    WrData[ST]      D=0x0000c560  B=0x200        /dev/disk0s3                                                                                                                                                  0.000198 W launchd.217
16:49:17.868382    WrMeta[AT]      D=0x00000002  B=0x200        /dev/disk0s3                                                                                                                                                  0.000242 W launchd.217
16:49:17.868629    WrMeta[AT]      D=0x005b1dd0  B=0x2000       /dev/disk0s3                                                                                                                                                  0.000475 W launchd.217
16:49:17.868964    WrData[AT]      D=0x02322210  B=0x1000       /dev/disk0s2                                                                                                                                                  0.000265 W launchd.217
16:49:17.869145    WrData[AT]      D=0x02322228  B=0x1000       /dev/disk0s2                                                                                                                                                  0.000433 W launchd.217
16:49:17.873292    WrData[AT]      D=0x011f9318  B=0x1000       /dev/disk0s2                                                                                                                                                  0.000241 W launchd.217
16:49:17.873526    WrData[SP]      D=0x00002388  B=0x200        /dev/disk0s2                                                                                                                                                  0.000264 W kernel_task.80179
16:49:17.940978  IOCTL             <DKIOCSYNCHRONIZECACHE>      /dev/disk0s2                                                                                                                                                  0.067438 W kernel_task.80179
16:49:17.941451    WrData[ST]      D=0x00009c73  B=0x10200      /dev/disk0s2                                                                                                                                                  0.000463 W launchd.217
16:49:17.956437  IOCTL             <DKIOCSYNCHRONIZECACHE>      /dev/disk0s2                                                                                                                                                  0.014963 W launchd.217
16:49:17.956625    WrData[ST]      D=0x00002388  B=0x200        /dev/disk0s2                                                                                                                                                  0.000187 W launchd.217
16:49:17.956696  sync                                                                                                                                                                                                         0.151608 W launchd.217
16:49:17.956860  getfsstat64                                                                                                                                                                                                  0.000005   fseventsd.437
16:49:17.956870  getfsstat64                                                                                                                                                                                                  0.000009   fseventsd.437
16:49:17.956890    WrMeta[AT]      D=0x00000002  B=0x200        /dev/disk0s2                                                                                                                                                  0.000253 W launchd.217
16:49:17.957194    WrMeta[AT]      D=0x00346068  B=0x2000       /dev/disk0s2                                                                                                                                                  0.000543 W launchd.217
16:49:17.957457    WrMeta[AT]      D=0x00363488  B=0x2000       /dev/disk0s2                                                                                                                                                  0.000796 W launchd.217
16:49:17.957678    WrMeta[AT]      D=0x0036dc68  B=0x2000       /dev/disk0s2                                                                                                                                                  0.001011 W launchd.217
16:49:17.957943    WrMeta[AT]      D=0x0036e7c8  B=0x2000       /dev/disk0s2                                                                                                                                                  0.001270 W launchd.217
16:49:47.987648  sync                                                                                                                                                                                                         0.029915   launchd.217
16:49:47.987816  getfsstat64                                                                                                                                                                                                  0.000004   fseventsd.437
16:49:47.987825  getfsstat64                                                                                                                                                                                                  0.000008   fseventsd.437
16:50:00.558773  exit                                                                                                                                                                                                         0.000066   mdworker.79984
16:50:00.558841  close             F=-1 [  9]                                                                                                                                                                                 0.000001   launchd.1444
16:50:00.558846  msync             A=0x0105553000        B=0x1000              <MS_SYNC>                                                                                                                                      0.000004   coreservicesd.414

I can tell you that the frequency at which the light blinks does not coincide with the print out from this command.... for example, the light is blinking as I type this but I get no output from /usr/bin/fs_usage :/