Hi, On Tue, 2017-11-21 at 18:35 +0100, Matthias Fischer wrote: > Hi, > > On 21.11.2017 15:42, Michael Tremer wrote: > > Hello, > > > > any progress on this? > > Not much, because I've been struggling with a flu for the past two > weeks, and its not over yet, but: > > In the meantime I ran several builds with different parameters. > > IMHO we could use: > > 'export XZ_OPT = --threads=0 -8 --memory=700MiB' > > in 'lfs/cdrom' > > and > > cd /install/packages/package/tmp/ && XZ_OPT="-T0 -8 --memory=700MiB" tar -c -p > --numeric-owner -J -f /install/packages/package/files.tar.xz * > > in 'lfs/Config'. > > Using '9' or '--extreme'-parameter brought no further improvements, > on the other hand, build time and RAM consumption increased > strongly. With '-8', minimal RAM consumption was about 680 MiB, using > '700 Mib' was always safe. So this is the minimum I would recommend. Yes, I observed the same thing. -9 compresses a little bit better and extreme doesn't change a bit. -8 seems to be optimal since it won't require too much memory to decompress either. So let's go with that. > Results: > > (Buildtime: 5 hours 20 minutes 59 seconds) > > 255866764 ipfire-2.19.1gb-ext4.i586-full-core117.img.gz > 252262006 ipfire-2.19.1gb-ext4-scon.i586-full-core117.img.gz > 175112192 ipfire-2.19.i586-full-core117.iso > > > -Michael > > > > On Tue, 2017-11-07 at 22:47 +0000, Michael Tremer wrote: > > > Hi, > > > > > > On Tue, 2017-11-07 at 19:41 +0100, Matthias Fischer wrote: > > > > Hi, > > > > > > > > On 07.11.2017 16:05, Michael Tremer wrote: > > > > > Hi, > > > > > > > > > > maybe this function helps: > > > > > > > > > > https://git.ipfire.org/?p=ipfire-2.x.git;a=commitdiff;h=5190eea24f9822 > > > > > a63d > > > > > c5d06d214b48f973b14f29 > > > > > > > > Thanks. I'll take a look... > > This would help, indeed, but how to implement(!?), and... (see below) Just run it somewhere in the script, figure out what is about 80% of that and if that is smaller than 800 MB, we should just fail. It would be good to have a function that determines the xz parameters and we use that where ever we call xz. We don't want any duplicated code. > > > > > On Tue, 2017-11-07 at 10:46 +0000, Michael Tremer wrote: > > > > > > On Mon, 2017-11-06 at 22:09 +0100, Matthias Fischer wrote: > > > > > > ... > > > > > > > > > > > > > > I forgot: Tuning the XZ-parameters... ;-) > > > > > > > > > > > > Good that you are bringing this up. So I think what we should do > > > > > > here is > > > > > > bringing back XZ compression with -8 so that we do not waste too > > > > > > much > > > > > > space > > > > > > when > > > > > > extracting the image again. > > > > > > > > Right now I'm testing how much RAM I need. > > > > > > > > Current 'next'-build is running with: > > > > > > > > 'lfs/cdrom': > > > > ... > > > > export XZ_OPT = --threads=0 -8 --memory=500MiB > > > > ... > > > > > > > > 'lfs/Config': > > > > ... > > > > cd /install/packages/package/tmp/ && XZ_OPT="-T0 -8" ... > > > > ... > > > > > > > > I'm waiting for the results. Takes a while. > > > > > > You can just run it like this and it will tell you: > > > > > > [ms(a)hughes ~]$ xz -vv8 -T0 > > > xz: Filter chain: -- > > > lzma2=dict=32MiB,lc=3,lp=0,pb=2,mode=normal,nice=64,mf=bt4,depth=0 > > > xz: Using up to 4 threads. > > > xz: 2,629 MiB of memory is required. The limiter is disabled. > > > xz: Decompression will need 33 MiB of memory. > > > xz: Compressed data cannot be written to a terminal > > > xz: Try `xz --help' for more information. > > > > > > > > > To not run into memory limits we should detect how much memory the > > > > > > build > > > > > > host > > > > > > has and set the memory limit to maybe 80% of that. xz will then > > > > > > automatically > > > > > > scale down to a number of parallel processes that it can fit into > > > > > > memory. > > This is something I couldn't get to work. First, I couldn't specify not less > than '700 MiB'. If I specify '600 MiB', building stops and tells me it needs > at least about 680 MiB. If I use '70%', building stops. And I never saw that > 'xz' "automatically scaled down". It just stopped everytime. Yes, ~700M is the minimum. It will just reduce the number of threads again to make sure everything fits into memory. > > > > > I'm a bit puzzled about this: I tried using '--memory=70%' as mentioned > > > > in the xz man pages, but is seems to have no effect. It looks as if the > > > > percent parameter isn't recognized and ignored. It always ends up in > > > > "cannot allocate memory". Any hints on this? Do both 'lfs/cdrom' AND > > > > 'lfs/Config' need the '--memory'-parameter? > > This was the next problem: 'percent'-parameter does not work as expected. No, don't use it. Just determine yourself what it is. I think we could even try to set 100% of the memory, because as far as I can see this is worst case and xz won't use everything that we allow. If that does't work, let's scale down to 90%, or 80%, etc... > > > Yes, but it would be good to have one place where the parameters are > > > being generated and then we just use them from a variable. > > Probably beyond my capabilities for the moment. Any thoughts? > > > > > > > ... > > > > > > We will at least need about half a GB which should be a sensible > > > > > > requirement > > > > > > for a build system any ways. > > I'm afraid '500 MiB' are not enough... No, so we will now make 1G the minimum for a build. I tried to build the OS on an ARM board with only 512MB of RAM the other day and even with a lot of swap it doesn't work. So we are past this any way. > > > > > Agreed. Because of this I'm testing with '500Mib'. > > > > > > > > > > Will you work on this bringing it into the build system?! > > > > > > > > "I'll do my very best!" :-)) > > > > > > Very well Miss Sophie... > > > ... > > Best™, > Matthias -Michael