My PC periodically reaches 100% SSD usage, and the entire system becomes extremely laggy. So far, this has only happened while I've been using After Effects, although I've been using it heavily lately and never experienced this issue before. In Task Manager, the System process appears at the top for disk usage when the slowdown occurs. Could this be related to running out of RAM, paging, scratch files, or Windows indexing, and what can I do to fix it?
3 Answers
Another possibility is Windows Search indexing, which scans files in the background and can temporarily use a lot of disk activity. You can check whether indexing is running when the slowdown occurs, but based on the timing and the System process being responsible, memory pressure and paging seem more likely.
After Effects may also be writing large cache or scratch files while Windows is paging memory to disk. That combination can overwhelm the drive. Check After Effects’ disk cache settings and consider placing the cache on a fast drive with plenty of free space. Clearing old cache files may help too.
The most likely cause is that your RAM is filling up. When that happens, Windows starts using the SSD as virtual memory through the page file, which can push disk usage to 100% and cause severe lag. Try closing other applications, reducing After Effects’ memory usage, or adding more RAM if this happens regularly.
So the main fixes would be using less memory or upgrading the RAM? I’ll check how much memory After Effects is consuming when it happens.

I’m not very familiar with indexing. I’ll watch Task Manager and see whether it coincides with the disk usage spike.