Is 100% CPU usage harmful while update-apt-xapi runs?

(System: 11.10 running Unity 3D)

When update-apt-xapi is running, CPU usage stays at 100% (for about a couple of minutes). Is that normal? I understand that the command runs update-apt-xapian-index to update the index of software packages.

My question is this: is such high CPU usage for a couple of minutes acceptable? (I have a Dell Inspiron 1545 laptop and the processor is "Intel® Core™2 Duo CPU T6400 @ 2.00GHz × 2 ")

If it could be harmful, what precaution can a non-technically proficient user take?

It is completely harmless. If it were to go on and on and on, you could run:

sudo killall update-apt-xapian-index

to save your CPU from frying :D, which is only likely to be a risk when your system has bad cooling.

To answer your "sub-question", it is not really "acceptable", so much as it is not what is ideal, but it is "acceptable" in the sense that it does not stay going for long enough to cause damage :).

Pro-tip:
When this program is running, stop doing what ever it is you are doing on the computer at the time unless it is critical/important, and if you have the cpu-frequency indicator, set it to performance for the moment, and let the application run through its paces. This way, it will finish faster, and your system will be smoother to use when it's over (because of less of a lock on the resources).

Could only be solved satisfactory with:

apt-get purge apt-xapian-index

This removed the faulty program from the system and I trust my laptop will not start to use 100% CPU and simultaneously trash hard drives again.

Listing some alternatives to the package removal solution.

• You can make /etc/cron.weekly/apt-xapian-index-update non-executable:

  chmod a-x /etc/cron.weekly/apt-xapian-index-update

• Alternatively, edit that script to pass the parameter --update to the update-apt-xapian-index command, so that it will update the index rather than rebuilding it. (For example, on 13.04, replace the parts $CMD --quiet with $CMD --update --quiet) (Source)

Note that removing the package (or preventing its execution) will not break the system, but it will slow down searches in Synaptic and APT. See also: "What kind of harm there is from removing (purging) package apt-xapian-index?"

Agreed that having your CPU usage at 100% for several minutes will not cause any harm.

You can always use:

acpi -tf

to check the systems temperature, if you are concerned.

Also, instead of killing the process you may want to try adjusting the priority of the process.

First find the process id:

pgrep update-apt-xapian-index

Then set the priority (-20 is highest and 19 is lowest):

renice 19 -p PID

That would set the update process to the lowest priority. It would take longer to finish, but would make the system usable while it is running.

I have run across an article which gives the code for making update-apt-xapi play nice, and reduce CPU usage. Read it here.

I haven't tested it personally yet, but I'm about to -- and the comment thread gives evidence of positive results.

Update - the article linked provides some lines to add/modify in the cron file to reduce CPU during update. As it turned out, those lines were already present in my case, so no help for me there. Might make a difference for others.