Photoshop CS4 does not release RAM

[Ide...@adobeforums.com]

I run Photoshop CS4 on a Windows PC with 4GB. Even though I frequently
"purge", Photoshop does not seem to be releasing RAM even when all files
have been closed, often holding on to some 2GB RAM. Only when I terminate
Photoshop, the RAM it grabbed is released. This means I would have to exit
and relaunch Photoshop many times a day.

Any suggestions?

[Free...@adobeforums.com]

This is normal and designed behavior, to avoid memory fragmentation. The RAM will be reused.

[Jim]

<Free...@adobeforums.com> wrote in message
news:59b7e...@webcrossing.la2eafNXanI...

> This is normal and designed behavior, to avoid memory fragmentation. The
> RAM will be reused.

And, even if PS did release the RAM, the OS might not honor the request.
Usually such cleanup only takes place when the program which requested the
memory shuts down.

Jim

[Chri...@adobeforums.com]

And there is no need to exit and relaunch Photoshop - the RAM is reused.

[Rob_K...@adobeforums.com]

the RAM is reused

Yes but since PS claims the RAM (for very good reasons, I agree) it seems only available to PS itself, so sometimes a plug-in (like PTlens) reports that it doesn't get the RAM it needs. Only one normal camera file is open.

After relaunching PS it works.

Sometimes RAM actually seems to get released within a session, why that happens, I don't know.

I have no problem with PS working this way. I appreciate PS wants RAM that's contiguous and thus doesn't was the O/S to hand it out, but some parts of the workflow call for external plug-ins to join in.

Rob

[John Joslin]

I thought that was the reason for never allocating too much to PS in preferences.

[Bart_...@adobeforums.com]

JJ: You are correct, and the OS will allocate more RAM to PS if it is required.

[Chri...@adobeforums.com]

Plugins have access to the RAM that Photoshop is using. They can tell Photoshop how much RAM they need, and Photoshop will free that. Or they can allocate buffers from within Photoshop's RAM.

Most of the plugins we have seen that have problems running out of RAM fall into 2 categories:
1) those working on the whole image at once and can't fit that into RAM
2) those that failed to read the Photoshop plugin SDK documentation on how to manage large buffers in RAM

[Michael Kalcevic]

When it spikes up to 1.9GB of RAM usage, it is a problem.

[Chri...@adobeforums.com]

Michael - how is that a problem? Photoshop reuses all that memory, and plugins can use it as well.

[Michael Kalcevic]

How is that Not a problem? With the amount of brush lag that I see, compared to CS3, there has to be an issue with the RAM usage.

[Chri...@adobeforums.com]

No, those probably aren't related at all.

You're seeing brush lag (not normal), and Photoshop using RAM up to the limit you set in preferences (very normal) and reusing that RAM (very normal).