[squeak-dev] A pretty big Squeak 4.3 image (nearly 8 GB)

Bert Freudenberg bert at freudenbergs.de
Sat Jan 14 16:18:23 UTC 2012


On 14.01.2012, at 17:09, David T. Lewis wrote:

> Here is a screen shot of the Squeak 4.3 release image traced to 64-bit
> object format, showing the image size after allocating a lot of object
> memory. This is running on a box with 8GB of real memory, so the image
> is about as large as can get on my computer.
> 
> <http://squeakvm.org/~lewis/squeak4.3-64bit/squeak64-big.png>

Yay!

> The image is fully functional and can be saved to disk and reloaded.
> Monticello and other tools all work, and the image can be updated from
> the trunk update stream as normal. Saving the image to disk and restarting
> it are slow due the file size and amount of memory used, but the image
> itself works fine. Garbage collection works, and overall the performance
> remains good up to the point that the operating system is forced to start
> page swapping (because the image is larger than available real memory
> on this box).
> 
> Dave

For reducing startup time, it might be a good idea to use the mmap trick of suggesting a target address. That way no oop adjustment is necessary on startup because the object memory would likely have the same base address. Pages are loaded on demand, so it would take until the first full GC to load the whole image into memory. IIRC, John got that to work on iOS.

- Bert -





More information about the Squeak-dev mailing list