Podpora :: RAR Support

2010-01-25 01:19:31
11p3G
Vypnuti prealokace na flash disk
Dobry den. Chtel bych se zeptat ci je mozne pri rozbalovani nastavit WinRAR pri GUI a SFX modulu tak, aby si nealokoval volne misto pro rozbalovany soubor. To spusobuje ze pri rozbalovani na zasifrovany nebo USB flash disk to trva 2x tak dlouho jak by melo.
2010-01-25 01:19:50
V.Mlich
Re: Vypnuti prealokace na flash disk
Predal jsem dotaz autorovi a zde je jeho odpoved:

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Now I removed this preallocation, but it resulted in more than twice lower performance when unpacking to my 8 GB USB flash disk, which is rather old though.

Flash disk performance strongly depends on a type of disk controller, so, I think, there is no universal solution suitable for all disks.

In general I think that progress is going on and controllers are becoming more intelligent, making any special optimization for flash disks less useful.

There is no way to switch this feature off for users. I just removed the preallocation code and recompiled RAR when testing it now.
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T.j. ze se to vypnout neda, ale ze to zkusil prekompilovat bez prealokace  a ja tam ctu, ze vykon klesnul (lower performance) na polovinu, tedy presne obracene?

V kazdem pripade mini, ze prizpusobovat program jedne z konstrukci radice neni spravna cesta. Tak se snad dockame klice, at si to uzivatele v pripade potreby mohou vypnout.

Pro jistou jsem se jeste zeptal, jestli nedoslo k omylu:

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> It means 'WITHOUT preallocation is the performance
> LOWER?', i. e.backwards as claims user?

Yes, exactly. And more than twice lower. I did not expect such difference myself. I expected that performance will be about the same before making this test.
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T.j. opravdu vypnuti prealokace ZPOMALI rozbalovani vice nez dvojnasobne, pry ocekaval, ze to na vykon nebude mit zadny vliv.

2010-01-26 18:35:31
11p3G
Re: Vypnuti prealokace na flash disk
Pri rozbalovani *.7z nealokuje volne misto. Kdyz rozbaluje male soubory tak jde trochu pomalu i na HDD.