hIOmon SSD Performance Monitor - Understanding desktop usage patterns.

[Anvil]

overthere,

This is the Control I/O w/MSDA metrics

I expect this could be the snapshot that's deleted.

vm_boot_build_shutdown_ICH_V260GB_3_trim.PNG

[overthere]

This is the Control I/O w/MSDA metrics

For those curious about what these MDSA-related metrics reflect:

• There were 5 MDSA control I/O operations that requested a TRIM
  
  
• The total combined number of "Data Set Ranges (DSR)" specified by these 5 TRIM control I/O operations was 19.
  
  A DSR identifies the starting offset (i.e., essentially the starting block address for the particular set of blocks/sectors) along with the overall combined length of the blocks/sectors to be "trimmed".
  
  
• The total combined length of the DSRs specified by these 5 TRIM commands was 1,611,800,576 bytes.
  
  
• The smallest DSR length observed amongst all of these DSRs was 4,096 bytes
  
  
• The largest DSR length observed amongst all of these DSRs was 1,610,612,736 bytes
  
  
• The lowest starting address (in bytes) observed amongst all of these DSRs was 1,232,896
  
  
• The highest starting address (in bytes) observed amongst all of these DSRs was 3,180,806,144
  
  
• The minimum total number of DSRs specified by a single TRIM control I/O operation was 1
  
  
• The maximum total number of DSRs specified by a single TRIM control I/O operation was 8
  
  
• The minimum total combined lengths of the DSRs specified by a single TRIM control I/O operation was 53,248 bytes
  
  
• The maximum total combined lengths of the DSRs specified by a single TRIM control I/O operation was 1,610,862,592 bytes

[Ao1]

For those curious about what these MDSA-related metrics reflect:

• The largest DSR length observed amongst all of these DSRs was 1,610,612,736 bytes

So in this instance the OS issued a single command to the SSD to wipe ~ 1.5 gigabytes of “deleted” data? I assume the SSD controller then waits for a quiet period and then deletes the data when it will have no/ less impact.


[Tiltevros] 16 Cores
I have created a separate thread for Winbootinfo otherwise this thread will end up way off topic.
http://www.xtremesystems.org/forums/...d.php?t=261924

[overthere]

So in this instance the OS issued a single command to the SSD to wipe ~ 1.5 gigabytes of “deleted” data? I assume the SSD controller then waits for a quiet period and then deletes the data when it will have no/ less impact.

Yes, and that is certainly one way that the SSD controller could handle the "backend" processing of the TRIM commands from the OS.

By "backend", I mean the actual manner in which (and when) the SSD controller performs various flash management tasks (e.g., wear-leveling) based upon the DSRs that it has received from the OS.

As you know, essentially the TRIM commands currently provide a way for the OS to notify the SSD that a specific set of (logical) blocks/sectors upon the SSD are considered by the file system to be "deleted data blocks" (that is, sectors upon the SSD that the file system considers to no longer contain valid data).

But as to what exactly the SSD does with these "trimmed" blocks/sectors (and when), this is, I believe, basically "vendor-specific" at the current time.