fs-fcache: Boot File Cache, boot faster.

iphitus · 2006-06-23 06:51:57

Hey,

Gave this a spin today:
http://marc.theaimsgroup.com/?l=linux-k … 814504&w=2

It's a boot cache mechanism. You boot a priming run where it caches to a partition, and all runs from then on, should boot at an improved speed. On my laptop, it dropped my boot from init>slim from 32s to 26s. 6 second improvement.

As an experiment, I left the priming run going while I logged in to my desktop. currently I'm using Gnome on this computer. The next boot, Gnome logged in so fast, the splash screen only flickered on the screen, and the panels appeared near instantly.

Bootchart before: http://archlinux.org/~james/normal.png
Bootchart after: http://archlinux.org/~james/fs-fcache.png

You can see the much more efficient use of the hard disk in the second run, with most slowdowns either being CPU bound, network bound or hardware related.

fs-fcache will be in 2.6.17-beyond1 which should hit the repos in the next few days, it's also in 2.6.17-ck1, which tomk has in [community] -- although I am not sure if he has it enabled. It currently only works for ext3, but other filesystems are trivial to implement and should come soon.

James

tomk · 2006-06-23 08:02:46

It's in kernel26ck 2.6.17.ck1-2, which will be in community in a couple of hours.

Skyscraper · 2006-06-26 19:14:58

Will be this feature implemented in GENERIC Arch kernel?

hehejo_ · 2006-06-26 19:49:36

That would be great!

But, how do you create these charts?

sh__ · 2006-06-26 21:30:22

hehejo_ wrote:

But, how do you create these charts?

pacman -S bootchart

hehejo_ · 2006-06-26 22:06:13

Too simple. Thank you.

funkyou · 2006-06-27 14:50:03

So, how do i activate this? Like described in the link above?

And what if i have several partitions (/ /usr /opt ...)?

Phrodo_00 · 2006-06-27 19:11:27

is this/when will this/will this be implemented in kernel26-beyond?. I just upgraded but I haven't rebooted yet. And I'm pretty sure I lost the gensplashbecause I don't know how to add it to mkinitfscpio

deficite · 2006-06-27 22:57:41

Do you know how long reiserfs users will have to wait to use this exciting feature?

iphitus · 2006-06-28 08:33:57

Phrodo_00 wrote:

is this/when will this/will this be implemented in kernel26-beyond?. I just upgraded but I haven't rebooted yet. And I'm pretty sure I lost the gensplashbecause I don't know how to add it to mkinitfscpio

This already available in 2.6.17-beyond1, but you have to add support to the initscripts yourself.

As for initcpio and gensplash, dtw should have the hook up soon.

tomk · 2006-06-28 08:51:11

deficite wrote:

Do you know how long reiserfs users will have to wait to use this exciting feature?

A few days ago, the dev said:

Jens Axboe wrote:

I hope to be able to extend it to xfs and reiser in the very near future as well, should not be hard to do.

sinisterguy · 2006-06-28 15:03:02

i've got a question about the fcache_dev parameter. The example on the page says 8/6. I'm assuming that means the 6th partition of the 8th device, but the page also mentions using sda6 as his cache partition. This is confusing. Input on that would be nice. Also i was wondering how big my cache partition should be.

somairotevoli · 2006-06-28 18:28:17

I too would like more indepth instructions. I would like to try this out, but I don't want to screw up anything. It seems simple enough. If someone could just provide a list of steps, I will be most grateful.

soloport · 2006-06-28 20:33:08

deficite wrote:

Do you know how long reiserfs users will have to wait to use this exciting feature?

Several minutes, each time it boots. LOL!

Ahhh. I kill me... Just kidding, k?

StormBlast · 2006-06-28 21:02:59

sinisterguy wrote:

i've got a question about the fcache_dev parameter. The example on the page says 8/6. I'm assuming that means the 6th partition of the 8th device, but the page also mentions using sda6 as his cache partition. This is confusing. Input on that would be nice. Also i was wondering how big my cache partition should be.

8/6 is not drive number/partition number but major device number/minor device number so 8/6 doesn't mean sda6 or hda6.
To find proper values for fcache_dev you can do, for example,

ls -l /dev/hda8

where hda8 is the disk you want use with fcache. This command gives you result

brw-rw---- 1 root disk 3, 8 2006-06-28 10:31 /dev/hda8

where numbers after "disk" are major and minor device numbers. In my example its 3 and 8 so fcache_dev=3/8.

deficite · 2006-06-29 17:26:57

Ahhh. I kill me

So I guess we shouldn't be expecting any more posts from you in the future then?

soloport · 2006-06-29 17:45:00

deficite wrote:

Ahhh. I kill me
So I guess we shouldn't be expecting any more posts from you in the future then?

You only wish :twisted:

barebones · 2006-06-29 18:02:33

I'm a bit confused about how to implement this. Do lines need to be added to the initscripts themselves, or could I just change my fstab? If so, what lines need to be changed? I'm a bit hesitant to rummage around in the init stuff, since I know next to nothing about them and would rather not totally bork my startup. A wiki page from one of you super smart fellows who have this going might be nice .

somairotevoli · 2006-07-02 23:09:15

So, Is anyone ready to help out with this?
Just a list of steps if possible?

tomk · 2006-07-03 08:58:53

I'm waiting for reiser support to give it a go - if nobody's put up a howto at that stage, I'll do it.

Here's an observation, though - this is about as bleeding-edge as you can get, and in the time-honoured tradition, the dev has given us the code with a brief guide on what to do with it. The essential details are all there for anyone who wants them, but it will be up to users to flesh it out.

IMO, if you want to try out new functionality like this, you have to take the risk that it won't work, and that you could "screw up" or "totally bork" your system. If you don't feel like doing that, then it's OK to wait a while - if you do, and it works, you can be the "super smart fellow" who writes the wiki page.

EAD · 2006-07-03 21:04:27

Can some one please give some more details about it???
I want to know it is work (technical details), and how to implemts it on my system, and will there be a good nice (like allways in ARCH) a WIKI page??
This seem to be a very nice cool EDGE thing :idea:

somairotevoli · 2006-07-03 21:52:50

I found a Gentoo HowTo here:
http://gentoo-wiki.com/HOWTO_FCache

I will give it a go, and maybe write my first wiki.

tomk · 2006-07-03 22:04:28

That's the spirit.

When you're writing it up, I'd recommend including StormBlast's advice above about finding the major/minor device numbers for the cache partition.

somairotevoli · 2006-07-03 22:30:28

^ I was thinking that's one of the most important steps. That was the first thing that confused me when I was first giving this a look over.

Well I think I got it running. I am about to do a boot chart to compare.

I also got into a little trouble by adding the cache partition to fstab which is not needed.

barebones · 2006-07-03 22:42:53

somairotevoli: which file are you actually editing? I've been looking through /etc/rc.sysinit, and I thought I found the entry to edit but fcache doesn't work. Dmesg says it fails with err: -6.

Arch Linux

#1 2006-06-23 06:51:57

fs-fcache: Boot File Cache, boot faster.

#2 2006-06-23 08:02:46

Re: fs-fcache: Boot File Cache, boot faster.

#3 2006-06-26 19:14:58

Re: fs-fcache: Boot File Cache, boot faster.

#4 2006-06-26 19:49:36

Re: fs-fcache: Boot File Cache, boot faster.

#5 2006-06-26 21:30:22

Re: fs-fcache: Boot File Cache, boot faster.

#6 2006-06-26 22:06:13

Re: fs-fcache: Boot File Cache, boot faster.

#7 2006-06-27 14:50:03

Re: fs-fcache: Boot File Cache, boot faster.

#8 2006-06-27 19:11:27

Re: fs-fcache: Boot File Cache, boot faster.

#9 2006-06-27 22:57:41

Re: fs-fcache: Boot File Cache, boot faster.

#10 2006-06-28 08:33:57

Re: fs-fcache: Boot File Cache, boot faster.

#11 2006-06-28 08:51:11

Re: fs-fcache: Boot File Cache, boot faster.

#12 2006-06-28 15:03:02

Re: fs-fcache: Boot File Cache, boot faster.

#13 2006-06-28 18:28:17

Re: fs-fcache: Boot File Cache, boot faster.

#14 2006-06-28 20:33:08

Re: fs-fcache: Boot File Cache, boot faster.

#15 2006-06-28 21:02:59

Re: fs-fcache: Boot File Cache, boot faster.

#16 2006-06-29 17:26:57

Re: fs-fcache: Boot File Cache, boot faster.

#17 2006-06-29 17:45:00

Re: fs-fcache: Boot File Cache, boot faster.

#18 2006-06-29 18:02:33

Re: fs-fcache: Boot File Cache, boot faster.

#19 2006-07-02 23:09:15

Re: fs-fcache: Boot File Cache, boot faster.

#20 2006-07-03 08:58:53

Re: fs-fcache: Boot File Cache, boot faster.

#21 2006-07-03 21:04:27

Re: fs-fcache: Boot File Cache, boot faster.

#22 2006-07-03 21:52:50

Re: fs-fcache: Boot File Cache, boot faster.

#23 2006-07-03 22:04:28

Re: fs-fcache: Boot File Cache, boot faster.

#24 2006-07-03 22:30:28

Re: fs-fcache: Boot File Cache, boot faster.

#25 2006-07-03 22:42:53

Re: fs-fcache: Boot File Cache, boot faster.

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