Why is windows 10 compressing memory when I have plenty available?

(EDIT: I have been asked to explain why my question is not a duplicate of this question. I thought the reason would be obvious from reading the two questions but to summarise: I don't have a memory leak. I know exactly what is using my memory. I am wanting to know why Windows is choosing to compress my memory (and hence use CPU cycles and render my system slow and unresponsive) when my system appears to have sufficient memory to store the entire application footprint in memory uncompressed.)

I do a lot of scientific/engineering computing simulation with bespoke and memory hungry applications. Perhaps not memory hungry in a 8tb supercomputer sense, but memory hungry in the 'more than word/email/youtube and even chrome' sense. Historically my worksets have occupied anywhere from 4-30 gb of RAM.

Since the anniversary update I have experienced significant performance issues with my machine, and while investigating I noticed that windows appears to be fairly aggressively compressing memory. For example, when opening a particular model I experience this:

Just to summarise the pertinent points from that screenshot:

• 15388 MB of memory in use


• 6855 MB of memory compressed


• If uncompressed, this would use 16657 MB


• 16.6 GB of memory free


• 32 GB of memory total

In short: If I didn't compress, by my understanding my memory requirements would be 15388-6855+16657 = 25190 MB. This is less than my available memory.

I have very often noticed that during times of reduced responsiveness my CPU is burning cycles doing memory compression like so:

I know that the concept of memory usage is extremely nebulous because of features like shared pages, reserved memory, copy on write etc etc but to me this situation looks like I'm just wasting CPU cycles and system responsiveness unnecessarily. My desire would be to simply not perform any memory compression and instead use my available RAM.

My questions are:

• Is there something I am misunderstanding that explains what Windows 10 is doing (because the current behaviour seems irrational)?


• Has there been a change in the behaviour/policy of memory compression since the anniversary update? I ask because I have only started experiencing these performance issues since the update.


• Is there a way to disable the memory compression? I have tried the technique described here without any luck.

Full disclosure: a version of this question was posted to the microsoft forum but only received canned replies, so I am reposting here.