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by mrguyorama 1111 days ago
I find that SSDs have a terrible failure mode too. Everyone thinks they are "fast" so they do all sorts of file operations that would have previously been considered too slow. However, consumer SSDs are only "fast" until they run out of DRAM buffer or SLC cache. Then they slow WAY down, like slower IOPS than my spinning rust disk. That means your busy machine goes from perfectly fine to nearly locked up, because even the OS now thinks file operations are "cheap" enough to block on and rely on in all sorts of hot paths.

Once that buffer or cache runs out, all those mostly extraneous IOPS just pile up, and the SSD will basically never catch up, because the technology fundamentally cannot catch up to a sustained load like that, but the load is sustained because all the software was designed with "SSDs are fast and lots of small writes will be fast" so they just keep growing the queue.

Previously most of the OS would be in memory and only page out if absolutely needed. It feels like modern windows is perfectly willing to page itself out because "SSDs are fast" and have random, pointless file ops everywhere. So if your SSD gets bogged down, now your operating system basically dies too, so good luck killing whatever app(s) are causing the problem