Re: [gentoo-user] Delays while building Libre Office.

[Alan Mackenzie]

On Thu, May 02, 2013 at 01:15:58PM -0400, Michael Mol wrote:
> On 05/02/2013 12:58 PM, Alan Mackenzie wrote:
> > On Thu, May 02, 2013 at 12:33:37PM -0400, Michael Mol wrote:
> >> On 05/02/2013 12:27 PM, Alan Mackenzie wrote:
> >>> Hi, Gentoo.

> >>> I've just built libreoffice-3.6.6.2 and it took 2 hours 10
> >>> minutes on my 2.6 GHz quad core Athlon 2.  It used to take about
> >>> an hour.

> >>> Watching the build, it became evident that the first 50 minutes
> >>> or so was taken up by several hundred mkdir operations (more
> >>> precisely, mkdir -p <long path>).  Some of these mkdir's would
> >>> take, perhaps, a minute to execute.  All the while, top showed
> >>> make taking 100% of one core.

> >>> There seems to be something suboptimal here.  Has anybody else
> >>> seen this, or does anybody have any ideas how to fix the
> >>> problem?

> >> Long delays suggest a timeout of some sort.

> > OK.  As a matter of interest, some of the mkdirs executed relatively
> > quickly - perhaps in 0.5 seconds.  I never saw the screen whizzing by
> > as I ought to have done, though.

> Hm.


> >> First thing I'd look at is the filesystem underneath, and the disk
> >> underneath that.

> > My /var is an ext3 LVM partition, doubled up on a RAID-1 disk array.

> How full is the ext3 partition? What options do you have enabled on it?
> (e.g. dir indexing?)

root@acm ~ # df /var
Filesystem         1K-blocks    Used Available Use% Mounted on
/dev/mapper/vg-var  12385456 1959860   9796580  17% /var

> > In the middle of the mkdiring, I checked there were enough inodes
> > free (there were).  I've no reason to suspect the disk drives might
> > be flaky.

> Well, you kinda do, now;

The reason I say this is that building the last ?one/two/three versions
of libreoffice also gave me this grief, but I haven't noticed anything
else amiss.

> you have evidence that at least some disk access is unusually slow.
> Check dmesg for disk I/O errors (unlikely to be reported at this point;

Nothing awry in dmesg.

> I'm sure you checked whether your RAID was in a degraded state),

cat /proc/mdstat shows everything in order.

> and run commanded smartctl tests on the disks.

That I haven't done, yet.

> >> Second thing I'd look at is to see if permissions checks might be
> >> bouncing through something like kerberos, samba or ldap. Do you
> >> have any single-signon things configured on that machine?

> > I've not got kerberos or samba installed.  I appear to have ldap
> > (whatever that might be ;-).  ls -lurt /usr/bin/ldap* shows these
> > binaries were last accessed (?used) on 2012-03-14.

> It would be more a question of whether they were tied into PAM.

OK.  I'm sadly ignorant about PAM.  :-(

> > What exactly do you mean by "single-signon"?

> Well, that was a slip of the tongue. More "central auth". I was
> wondering if there were any features installed on your system that are
> designed to check authorization against a server somewhere. (i.e. you
> can use an LDAP directory to centrally manage things like users, groups,
> etc.)

Not that I know of.  My machine is a mere desktop connected via a
router/modem to the net.  I'd have no reason to install any auth stuff.

> Technically, single-signon combines authorization checks with persistent
> authentication checks. Examples of this include kerberos, web session
> cookies and some uses of OAuth; once you're authenticated, the mechanism
> ensures you don't need to authenticate to another server in the same
> auth realm so long as your existing session hasn't expired. But this is
> less likely to be related to your problem than something seeking to ask
> a server if you have authorization to access something.

If this were the case, what would libreoffice's build need to ask that no
other package stumbles over?

-- 
Alan Mackenzie (Nuremberg, Germany).