Trim Support for Guest OS XP

[JeremyM1]

I am running Windows XP Pro SP3 guest on Snow Leopard 10.6.8 host on Parallels Desktop 8. I have bought PD11 Upgrade, but cannot install it on Snow Leopard, and holding fire on El Capitan until it is better than Snow Leopard. I have recently fitted an SSD Sandisk Extreme Pro. I am running Trim Enabler on Snow Leopard

Since running a sound processing app on XP, I notice my virtual drive is ballooning in size - going from 43GB to 60GB after one session. I suspect that files deleted on xp are not actually finding their way off the virtual drive - a feature of SSD. Normally garbage collection is done on the drive, but only I suspect on the OS X drive, not the virtual drive, which is recognised just as one very large file.

XP does not support Trim natively, but I believe there are third party patches available. Should it be done this way, or is there a way to trim an SSD through Parallels Desktop and free up deleted file space on the virtual drive? Perhaps some way to talk to the Trim command on the Mac.

 

[JeremyM1]

The problem may be with SmartGuard snapshots. When I set up Time Machine, I excluded the pvm file because it was filling up my backup drive, hoping to use TM-friendly snapshots to backup changes under my guest OS. It solved the problems of TM filling up my backup drive, but seems now to have bloated the virtual drive. The virtual drive cannot compress itself while there are snapshots present.

So I have turned off SmartGuard, manually deleted all the snapshots and then reclaimed disk space with dramatic results:

Before Finder reported on my SSD - 164.63 GB used, 75.08 GB remaining
After deleting snapshots - 140.09 GB used, 99.63 GB remaining
After reclaiming disk space - 124.74 GB used, 114.97 GB remaining

I can rely on OS X's Trim to do the necessaries cleaning up the SSD. I am anxious to keep the disk space down to something I can fit on a 128 GB bootable USB stick, for when I get round to upgrading OS X, and need a bootable backup.

For now, I will have to back up the virtual drive manually, copying the last working copy of the pvm file and deleting the one before. I cannot see any other way of doing incremental backups of the virtual drive, but welcome suggestions.