Konstantin Ryabitsev wrote: > On Sun, 02 Jan 2005 21:59:58 +0100, Farkas Levente <lfarkas@xxxxxxxxx> wrote: > >>just try out a: >>time yum -C list mtr >>it has nothing to do with the network and the speed is almost the same! > > > In my experience it isn't, but then again, doing "yum list \*mtr\*" > only takes 8 seconds on my laptop. If it takes longer on other > machines, considering mine is certainly not the fastest of the bunch, > my suspicion is that the slowdown is not dependent on the processor. > Memory and network would be my suspects. > > >>it seems there are two place where yum is very slow: >>- loading the local metadata (even if using the pickle files) >>- the dependencie resolution >>probably it needs to investigate further what is the real reason and how >>can be solve. if yum be so slow for a long time, there will be someone >>who create another package using a better/more clever local cache file >>format and and may be reimplement it in a faster language (may be a >>better/faster server side metadata format). [skip] > Feel free to encourage anyone to come up with a system better than yum > that doesn't do things the apt way, i.e. doing everything outside of > RPM and then just making a system call to the binary. I believe anyone > attempting to re-implement yum will soon run into exactly the same > problems as those faced by Seth et al. If someone does come up with an > application that functions speedily and covers the same robust set of > features that yum provides, then I'm sure Seth will have no problem > stepping aside and letting the poor bastard who replaces him to take > all the abuse. In fact, as someone for whom Seth is a direct > supervisor, I'll downright encourage that development. :) > > However, I believe that until RPM is replaced with an able enough > alternative, things will not dramatically improve, however much you > desire them to, and however many times you rewrite yum. Feel free to > prove me incorrect. first of all i do NOT like to blame anyone especially not seth since i like yum as the only usable tool. but that doesn't mean i can't tell my point of view and my critics. in short: - yum is slow (rather slow) and it can (and i hope will) be faster! imho it's better to not show any kind of exmaples, but - even if nothing changed on the system (add/remove) like in case of list it takes a long time to get the result. - even when only package name, version, release, epoc information will be enough (which is the most usualy case!!!! ie. yum install/erase/update/check-update/list) it load, parse and build python's object from all data which is about 95-99% is waste of resources (time and memory). this is just my estimation based on that the rpm filename is longer than the EVR string and only the pickle file is loaded: ----------------------------------- # ls /mnt/download/mirror/fedora/3/i386/os/Fedora/RPMS/|wc -c 48537 # ls -l /var/cache/yum/os/ total 6252 drwxr-xr-x 2 root root 4096 Dec 20 18:48 headers/ drwxr-xr-x 2 root root 4096 Nov 12 10:06 packages/ -rw-r--r-- 1 root root 816171 Nov 4 00:22 primary.xml.gz -rw-r--r-- 1 root root 5532228 Nov 12 10:06 primary.xml.gz.ce7bdfd5a6066a4f18c498b693faa16597a0733c.pickle -rw-r--r-- 1 root root 1140 Nov 4 00:22 repomd.xml ----------------------------------- and to show a much slower case when someone use more repos: --------------------------------------------- # cat /proc/cpuinfo /proc/meminfo processor : 0 vendor_id : GenuineIntel cpu family : 15 model : 2 model name : Intel(R) Pentium(R) 4 CPU 2.20GHz stepping : 4 cpu MHz : 2222.143 cache size : 512 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm bogomips : 4374.52 MemTotal: 1035124 kB MemFree: 108180 kB Buffers: 98368 kB Cached: 589540 kB SwapCached: 12 kB Active: 687336 kB Inactive: 185700 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 1035124 kB LowFree: 108180 kB SwapTotal: 2008084 kB SwapFree: 2006912 kB Dirty: 63892 kB Writeback: 0 kB Mapped: 430524 kB Slab: 26996 kB Committed_AS: 831304 kB PageTables: 6096 kB VmallocTotal: 3088376 kB VmallocUsed: 3672 kB VmallocChunk: 3084504 kB HugePages_Total: 0 HugePages_Free: 0 Hugepagesize: 4096 kB # time yum -C list mtr Setting up Repo: dag Setting up Repo: freshrpms Setting up Repo: jpackage16-generic Setting up Repo: jpackage16-fc3 Setting up Repo: updates Setting up Repo: Newrpms Setting up Repo: addons Setting up Repo: os Setting up Repo: pre-extras Reading repository metadata in from local files dag : ################################################## 1531/1531 freshrpms : ################################################## 456/456 jpackage16: ################################################## 1277/1277 jpackage16: ################################################## 19/19 updates : ################################################## 407/407 Newrpms : ################################################## 374/374 addons : ################################################## 10/10 os : ################################################## 2622/2622 pre-extras: ################################################## 630/630 Excluding Packages in global exclude list Finished Installed Packages mtr.i386 2:0.65-1.1.fc3.rf installed real 0m39.976s user 0m11.271s sys 0m1.030s --------------------------------------------- -- Levente "Si vis pacem para bellum!"
