hIOmon SSD Performance Monitor - Understanding desktop usage patterns.

[Ao1]

Here I monitor Call of Duty Black Ops Single Player for 30 Minutes. I monitored the specific folder Call of Duty at a 1 minute interval. The first surprise is the amount of processes that were generated, which are summarised below. All contributed to numerous random and sequential read requests over the 30 minute duration to varying degrees. 64 processes generated 1,127 individual reads.

Games are not all about sequential reads, random read speeds seem to also be important.



Read speeds


IOP Count


Fast Read IOP count. Worst case percentage = 1%. Average 98%.


Queue Depth - Maximum Max = 5

[Ao1]

Here I show around 1 ½ hours of activity on the page file with the size set automatically by Windows.

During the monitoring period I ran most of the typical programs I use all the time, including:

• Large and small Photoshop files (2MB to 2.3GB)
• Web browsing with 7 pages open. (IE9 and Chrome).
• Traktor Scratch
• WMP
• Checked emails and cleaned up the in box
• Black Ops MP
• Worked on an Word document
• Worked on an Excel document

On average Windows Task Manager recorded around 64 process running.
OS = Win 7/64 with 8GB RAM.

[IanB]

The figures tell the story.

You have 8GB of memory, the biggest file you opened in Photoshop was around a quarter of that, yet despite all that spare RAM the system saw fit to dump a piddly 280Mb of data to pagefile - just in case? But this data clearly wasn't needed again, since it only read back in 90Mb tops.

The pagefile activity you showed was totally redundant. The system wastes time using it if it is there, so it's simpler and more efficient to monitor your maximum Commit Charge for your working set of apps and data over time, then make sure your RAM is more than enough to cover that and turn the pagefile off instead.

Plus, anyone who follows the archaic Microsoft dogma of sizing the pagefile as 1.5 x RAM (with large amounts of installed RAM) is a fool who's simply wasting disk space. Just turn off the system error dump since you'll never use it if you do ever bluescreen.


EDIT: I admit, I ran out of memory the other day. But that was a fault with Media Player Classic buffering a large, damaged video when I tried to skip through it. I watched the Virtual Memory Commit Charge spiral out of control in Process Explorer, so it was a bug in Media Player or one of its components, not a fault in my choice of turning off pagefile, since likely it would have continued on to use whatever pagefile I'd provided too and hit the limit of that.

There will always be exceptions, but this doesn't change the obvious best practise that Ao1's example proves.

[Ao1]

EDIT: I admit, I ran out of memory the other day.

That is the only reason I can think that MS would still recommend using the pagefile. What I could see over 1 1/2 hours is exactly as MS describe for why you should use the pagefile with SSD. A predominance of small random reads and large sequential writes, which an SSD can handle very well. The bottom line however is that RAM can hangle it better and it saves data being pointlessly writtten to the SSD.

I’ve left the pagefile.sys script running so later today I will post the Excel summary sheet for anyone that is interested.

On a separate issue here is a summary of Anvil’s monitoring.

[Ao1]

Attached is the pagefile log after 7 hours of use.

[IanB]

That is the only reason I can think that MS would still recommend using the pagefile.

To cope with buggy programs that develop a 4GB memory leak in seconds, and likely wouldn't have stopped leaking if I'd had gigs more?

[Ao1]

Here I monitor Call of Duty Black Ops Multi player.