[Phssthpok]

I find that as I edit books, my system gets slower and slower. Usually I find that there are many processes running callibre-parallel.exe. At the moment, after a reboot, I have imported a couple of books, viewed them, deleted one, and edited one, and am now editing the other. I saved it yesterday, closed the lid of my laptop and went to bed. Today I've opened up the system and have been dealing with mail and so on, but the system is already starting to thrash a bit. I find that currently have 5 calibre-parallel.exe processes with the following command lines:

1. "C:\Program Files (x86)\Calibre2\calibre-parallel.exe" --pipe-worker "from calibre.utils.recycle_bin import recycler_main; recycler_main()"
2. "C:\Program Files (x86)\Calibre2\calibre-parallel.exe" --pipe-worker "from calibre.utils.ipc.pool import run_main, worker_main; run_main(worker_main)"
3. "C:\Program Files (x86)\Calibre2\calibre-parallel.exe"
4. "C:\Program Files (x86)\Calibre2\calibre-parallel.exe" --pipe-worker "from calibre.gui2.tweak_book.completion.worker import run_main, main; run_main(main)"
5. "C:\Program Files (x86)\Calibre2\calibre-parallel.exe"

The 3rd process is the parent of the last 2.

I don't know if this is strictly an editor issue, but can anyone explain why these processes seem to just just hang around and increase in number as time goes on?