7zip Memory Problem

HandsomeGuy

There was an issue with PA not being able to compress VERY large files in 7z format, where it would just quit the compression without any warnings watsoever. Also, it took too much memory that Windows always complaied of Virtual Memory being low.

Are those two problems fixed in Beta 3?

spwolf

Bug with 7zip just quiting was fixed in 9.5.

Memory used is still the same - if you select Ultra setting, 7zip will want 400 MB available - thats not something that can be changed since dictionary used is large and thats how 7zip manages to create smaller files. Thats why PA by default uses Maximum setting which is much less memory demanding.

HandsomeGuy

If Ultra wants 400MB, how does does Maximum need?

Also, is there a HUGE difference between ultra and maximum? Well, anything worth the extra slowness. BTW, how much faster is maximum compares to ultra?

spwolf

@HandsomeGuy:

If Ultra wants 400MB, how does does Maximum need?

Also, is there a HUGE difference between ultra and maximum? Well, anything worth the extra slowness. BTW, how much faster is maximum compares to ultra?

Maximum needs some 280-300 MB less :-).
Difference in size is our around 10% on average.

In any case, it is not as if you will be playing some game and compressing files, so I do think that for most of the things you will be fine with Ultra, except for compressing 10 gb of data at the same time, which might take a lot longer.

regards,

HandsomeGuy

I have been trying to compress XBOX game backups with PA, and it basically NEVER works. Its so damn slow, and even before finishing, I get the low virtual memory messages.

I use WinRAR and they get compressed just fine. Sure that also takes time, but it has never come back with any memory low error.

I’d really like to use PA to get the smallest 7z file I can, but looks like that won’t be happening anything soon.

PS: The XBOX games are on averge about 4gb each with plenty of files/folders.

davidsplash

you are comparing rar to 7zip which is still being developed ?

HandsomeGuy

@davidsplash:

you are comparing rar to 7zip which is still being developed ?

So what format would you suggest would be best for such big jobs as this? I want something with good compression, that isn’t slow as a dog.

spwolf

@HandsomeGuy:

I have been trying to compress XBOX game backups with PA, and it basically NEVER works. Its so damn slow, and even before finishing, I get the low virtual memory messages.

I use WinRAR and they get compressed just fine. Sure that also takes time, but it has never come back with any memory low error.

I’d really like to use PA to get the smallest 7z file I can, but looks like that won’t be happening anything soon.

PS: The XBOX games are on averge about 4gb each with plenty of files/folders.

Only solution is to up your virtual memory or use maximum setting instead of Ultra. Maximum should still be 5% better than WR Max.

I dont see where the problem is - if you get memory too low error, then you simply up the virtual memory. If you dont want to use more virtual memory, then use lesser setting.

Does the XBOX ISO file even compress?

HandsomeGuy

@spwolf:

Only solution is to up your virtual memory or use maximum setting instead of Ultra. Maximum should still be 5% better than WR Max.

I dont see where the problem is - if you get memory too low error, then you simply up the virtual memory. If you dont want to use more virtual memory, then use lesser setting.

Does the XBOX ISO file even compress?

I don’t compress the ISO file. I uncompress the ISO and then compress all the files. It does compress with WinRAR fairly well.

Carlospr

@spwolf:

Bug with 7zip just quiting was fixed in 9.5.

Memory used is still the same - if you select Ultra setting, 7zip will want 400 MB available - thats not something that can be changed since dictionary used is large and thats how 7zip manages to create smaller files. Thats why PA by default uses Maximum setting which is much less memory demanding.

I think PA should use “Normal” (+solid) setting as a default for 7zip.

It seems that 7-zip (the software) uses “Normal” (+solid) as its default operation.

That’s why 7-zip (the software) seems to be a lot faster than PA (using context menu).

HandsomeGuy

But what about better compression?

Carlospr

For the files I’m working with the compression difference is really little (~7KB)…

But “Normal” takes almost half of the time compering with Maximum or Ultra…

HandsomeGuy

Well, PA 7z files take a VERY long time to finish. I’m talking on average og compressing 4gb. I use WinRAR for those huge tasks, and 7z for smaller tasks.

Carlospr

I don’t work with such big files… Have you tried to use 7zip and Normal compression with those huge tasks?

HandsomeGuy

Briefly, yes. But its still too slow, and theres memory problems that have happened before, which makes me fearful in trusting my important games files to the 7z and PA combination.

spwolf

@Carlospr:

I think PA should use “Normal” (+solid) setting as a default for 7zip.

It seems that 7-zip (the software) uses “Normal” (+solid) as its default operation.

That’s why 7-zip (the software) seems to be a lot faster than PA (using context menu).

whole point of 7zip is extra compression. If speed is the issue and size does not matter, ZIP is much better and faster solution than both 7zip or WinRar.

Eventually, you will be able to select default settings for compress to name.format in shell extensions, so you will be able to do that yourself.

regards,

TBGBe

@HandsomeGuy:

So what format would you suggest would be best for such big jobs as this? I want something with good compression, that isn’t slow as a dog.

There are two good sites which give comparisons - but they have not been updated for a long time:-

ACT http://compression.ca/
Comparisons http://www.rojakpot.com/default.aspx?location=3&var1=4&var2=0

But the only way to really find out which is best for you is to do some testing yourself using the type of data you will be wanting to compress.
A general rule of thumb is :-
Smaller Size = Longer Time + higher System Requirements.

For you, the System is fixed (your P.C. configuration) but only you can decide “how much time” is worth “how much compression”.

Carlospr

@spwolf:

whole point of 7zip is extra compression. If speed is the issue and size does not matter, ZIP is much better and faster solution than both 7zip or WinRar.

Eventually, you will be able to select default settings for compress to name.format in shell extensions, so you will be able to do that yourself.

regards,

I understand your point.

However, the size difference (between Maximum+Solid and Normal+Solid) is so small (at least for the files I use to work - 7KB) that it’s worth to get a bigger file but a real faster process (almost half of the time with NOrmal+Solid).

Even 7z Normal+Solid makes a smaller archive than WinRar.

Anyway, I think you have a great solution. It’ll be great to select the default settings for compress name.format in shell…

davidsplash

its not pa’s fault 7zip is still being developed the best format to use would be uha but i not supported by powerarchiver yet.

the best format that pa supports is 7zip but zip close to that in terms of use.

Its up to you but 7zip memory problem is due to indows and what ram you have. Tests have shown on one computer with 256mb ram to be better than one with 512mb ram cquse it uses windows 98 instaed of xp just shows you the problem the makers of pa and 7zip have.

HandsomeGuy

Well, bring on UHA format support then.