I noticed that if I manually enter a 7z file (I mainly use 7z archives, but the problem may include .zip files and others) and select some files inside, then drag and drop them to another folder, the process is considerably slower (like, it takes 5 times longer) than if I just right click on the file and extract all the files in the same folder or even if I drag and drop these files in their parent folder.
In my case when I tested this, "another folder" is in the same library (as I described here: Extract to... library sub-folder bug), but on a different partition on the same physical HDD.
Any news about this problem? The unzip is still considerably slower if you drag and drop selected files from a 7z file than if you extract all the files first, then select the files you need.
The 7zip format can be very inefficient for random access - reading a single arbitrary byte from the archive can often require decompressing megabytes of data before it, depending on how the archive was created.
I think there's a problem when copying out of an archive which is in a library. Opus is extracting each file individually instead of doing them all in a batch.
) have fixed that for the next update.