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Can someone explain this?
Extracting something with 7zip on an SSD and it's just 35 mb/s. What is bottlenecking here when task manager shows that pretty much everything is not even close to its limits.
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>>60115300
Windows.
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>>60115300
Run the built-in benchmark. If it's still shit, you'll know what the problem is.
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Is 7z multithreaded? If it isn't, are you sure you aren't maxing a core?
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>>60115375
It works well with multi-threading if you use high or lower compression, but ultra compression under utilizes CPU severely. That's for compression. I don't know about decompression.
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>>60115399
I'd imagine that compression is highly parallelizable, as you can scan the file in whatever order you want for common patterns. decompression seems more sequential in nature.
>7-zip supports multithreading decompression only for bzip2.
also
>About LZMA decompression.
>i7 3.46 GHz can decompress with speed about 15 MB/s of compressed. If compression ratio is 1/3 it's 45 MB/s of uncompressed data.
OPs results seem more or less reasonable.
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>>60115431
>>7-zip supports multithreading decompression only for bzip2.
So that's why my passthrough took half an hour to compress what my host did in 60 seconds...
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>>60115361
that one runs fine
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>>60115300
Would be pretty surprised if default behavior was to hog 100% of available CPU and make everything else grind to a halt
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>>60115375
>Is 7z multithreaded?
According to taskmanager it was using all 4 cores, but only to ~30%
>>60115431
Yeah, the file is LZMA:24
But what is the limiting factor here, is it really the CPU?
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>>60115431
>>7-zip supports multithreading decompression only for bzip2.
That is a 7 year old post from Igor btw, so I suppose by now it does use multiple threads as the task manager shows it
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>>60115666
That's how windows processes operate. The saving grace is that most processors are multicore so each process can at least take up max the entirety of it's own core. Unless it's a multithreaded/process application. There is some sort of scheduling happening per core as well but it's mostly ignore-able for foreground tasks which are given higher priority.
Generally it's desirable to allow an application to finish it's task as soon as possible with as much resources that are available to it though you may have a task that even though it's foreground may want higher priority (windows task manager photo attached).
On that vein... does anyone know if it's possible for an application to set it's windows scheduler priority through code?
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>>60115761
Im just guessing it wouldnt be popular if extracting your 100gb archive from tpb effectively made your computer unusable for a day.
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extracting an archive that was compressed with "fastest" preset is also not faster.
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but the "saving" preset decompresses blazing fast ofc, so drive can be left out as the bottleneck I guess
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