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Postings by Clemens Eisserer

Was APLM accidently enabled in Fedora 27?

Hi,

Since a week or so my laptop has severe SATA issues when running on
battery-only.

Was APLM enabled by accident in Fedora-27 (I know there are currently
experiments going on for Rawhide / F28):
<a href="https://bugzilla.redhat.com/show_bug.cgi?id=1543493" title="https://bugzilla.redhat.com/show_bug.cgi?id=1543493">https://bugzilla.redhat.com/show_bug.cgi?id=1543493</a>

Best regards, Clemens

Fedora 27 ships with outdated intel driver from 20160929

Hi there,

For Fedora 26 (or was it 25) it was decided to replace the
intel-optimized xorg-x11-drv-intel with the generic modesetting+glamor
approach.
While this works well for >= Sandy-Bridge (gen6) based chips, I
experience performance regressions for day-to-day work (eclipse,
libreoffice, ...) on my gen5 laptop and I suspect gen4 (i965) is even
worse.

Therefore, I continue using xorg-x11-drv-intel + SNA, however, the
package shipped by Fedora is really outdated and now over a year old
(20160929): <a href="https://bugzilla.redhat.com/show_bug.cgi?id=1496252" title="https://bugzilla.redhat.com/show_bug.cgi?id=1496252">https://bugzilla.redhat.com/show_bug.cgi?id=1496252</a>

I don't expect active support for this se

OOM-Killer is active on Nokia 770 despite >128mb of free swap

Hi,

I would like to use my Nokia 770 running OS2008HE as home server,
running debian wheezy (with a recompiled eglibc for linux-2.6.16
compatibility).
However, despite 256mb swap (swappiness=1) the OOM killer frequently
kills processes.

Was the Nokia 770 kernel patched with some kind of "enhanced" memory management?
Are there any known work arrounds, so that the sum of all processes
may exceed the amount of available ram?

Thank you in advance, Clemens

Reasons for postgres processes beeing killed by SIGNAL 9?

Hi,

Recently single postgres processes are killed by SIGNAL 9 on our
virtual vvmware managed server without any manual interaction -
causing lost transactions.
Any ideas what could be the reason?

Is there a tool for checking database integrity

Hi,

Is there a tool for checking a postgresql database for integrity, so I
would be notified immediatly if something went wrong e.g. with memory
and can go back to the last good backup?
Such a tool would guarantee me I am not sitting on a ticking time bomb
(corrupted database) without even noticing it.

Thank you in advance, Clemens

Will using a PreparedStatement only once introduce additional round-trips compared to a simple text-only query?

Hi,

When using prepared statements only once, will there be additional
roundtrips required between jdbc-client and postgresql-server in order
to prepare the query? Will there be a lot of additional data
exchanged?

The application I am developing uses Hibernate as middleware which
uses PreparedStatements a lot, however because I ran into a few
problems with PreparedStatement caching I plan to disable caching,
which will lead to quite a few PreparedStatements only used a single
time and recreated each run.

Thank you in advance, Clemens

Any disadvantages of using =ANY(ARRAY()) instead of IN?

Hi,

I am using postgresql as database for a hibernate based java oltp
project and as in previous projects am totally impressed by
postgresql's robustness, performance and feature-richness. Thanks for
this excellent piece of software.

Quite often Hibernate ends up generating queries with a lot of joins
which usually works well, except for queries which load some
additional data based on a previous query (SUBSELECT collections),
which look like:

select ..... from table1 ... left outer join table 15 .... WHERE
table1.id IN (select id .... join table16 ...

Can't connect as non-root user to database

Hi,

All I would like to do is the create a small database with a non-root
user which is allowed to access the db, however after hours of trying
I gave up.
I am using MySQL-5.5.20 on Fedora16 .

CREATE USER 'someone'@'%' IDENTIFIED BY 'somepass';
CREATE DATABASE somedb;
GRANT ALL ON somedb.* TO 'someone' IDENTIFIED BY 'somepass';
FLUSH PRIVILEGES;

However, when I try to log in to somedb using someone, I always get:

mysql --user=someone -p somedb
Enter password:
ERROR 1045 (28000): Access denied for user 'someone'@'localhost'
(using password: YES)

Any idea whats going wrong here?
Connecting

Initdb fails on openwrt in "creating template1 database"

Hi,

I try to run postgresql on my mips based openwrt router.
Although openwrt provides precompiled packages, I have troubles
initializing postgresql's file system:

# creating template1 database in /var/postgresql/data/base/1 ...
FATAL: could not write to file "pg_xlog/xlogtemp.1791": No space left
on device

There are about 800mb free space on /, any idea what could be the problem here?
The only strange thing I noted was, that the openwrt package was
shipped without a postgresql.conf - whereas a default configuration is
part of both, SuSE and fedora packages.

Thank you in advance, Clemens

How to diagnose application "hangs" in pg_receive?

Hi,

A hibernate based application I wrote suffers from "hangs" - the
thread which should fetch the data is stuck at pg_receive (the
function reading back data from the socket).
My first idea were threading errors, however after careful code review
I couldn't find suspicious code.
The application doesn't do any explicit locking, an excerpt of the
locking table is at the end of the email.

Any idea what could be going wrong here?
Except a broken connction, what could be the reason for never arriving
reply from the server?

Thank you in advance, Clemens

datname | relname

hash semi join caused by "IN (select ...)"

Hi,

I have a quite complex, performance sensitive query in a system with a
few (7) joins:
select .... from t1 left join t2 ....

BEFORE UPDATE trigger also fires at insert?

Hi,

I've defined a small trigger to increment a field each time the row is updated:

Works quite well, however the trigger is also fired if the table
itself is modified.
When deleting or inserting a single row, the trigger is executed for
all rows contained in the table.

Is this intetional, and if so, how can I get the behaviour to only
execute the trigger when an update on the relation is performed?

Thank you in advance, Clemens

Could somebody please have a look at Bug 265051?

Hi,

I usually wouldn't bother the mailing list with requests for bug
fixes, however this bug is really a show-stopper for
people using kde with different resolutions (like laptop users with an
external monitor), and as far as I've seen there was not a single
comment from a KDE developer.
It would be great to see it fixed in 4.6.x, before people are plagued
by bugs introduced in 4.7.

When the panel width exceeds the monitor's resolution, it isn't resized.
Wouldn't be too bad, however the config cashew is on the right side -
so the only work-arround I found was to remove the panel and re-creat

KDE Quality (problems)

Hi,

I use KDE since 1998/1999 with kde-1.1 beeing the first version I
remember having used.
I always found it to be simply the best Desktop Environment,
escpecially during KDE-2.x/3.x times.
Since KDE-4 I am not that happy anymore. Early releases were
horrible, ~4.3/4.4+ is ok, but still not as solid as one would expect.

The problems I see are:
1. Too few developers, too much code
2. Too short release cycles & Quality testing
3. Features count most mentality.
4.

Howto use "COPY FROM" with the native API?

Hi,

We are working on an university project for network traffic accounting.
We use ulogd-2 to log netfilter packets, however it creates for each
packet a seperate transaction and also doesn't use prepared
statements, which results in horrible performance.

What we are looking for is a low-overhead way of inserting many rows
(100-1000) into a table at once in one transaction.
Is "COPY FROM STDIN" a good idea in this case?

If so, are there some examples how to use "COPY FROM STDIN" with the
native C API?
I found some documentation, however as I am no C native some sample
code would really hel

Howto use "COPY FROM" with the native API?

Hi,

We are working on an university project for network traffic accounting.
We use ulogd-2 to log netfilter packets, however it creates for each
packet a seperate transaction and also doesn't use prepared
statements, which results in horrible performance.

What we are looking for is a low-overhead way of inserting many rows
(100-1000) into a table at once in one transaction.
Is "COPY FROM STDIN" a good idea in this case?

If so, are there some examples how to use "COPY FROM STDIN" with the
native C API?
I found some documentation, however as I am no C native some sample
code would really hel

Howto sort the result of UNION (without modifying its type)?

Hi,

I have a query where I UNION several select statements which return
IDs of type INTEGER.
This works well, if the IDs don't need to be sorted:

However I need the result the UNIONs to be sorted, so I tried the following:

Slow query execution over WAN network

Hi,

I experience really slow query execution over remote networks,
especially for a query which returns a lot of columns (~255) caused by
joins.

Executing the same query over different networks gives the following times:
Local: 20ms
DSL: 400ms
UMTS: 1500ms

The query returns 12 rows, and 255 column - most of them with only
very little data.

Slow query execution over high latency network

Hello,

When executing huge (10kb), hibernate-generated queries I noticed that
when executed remotly over high-latency network (ping to server
200-400ms), the query takes a lot longer to complete.

When the query is executed remotly (psql or jdbc) it takes 1800ms to
execute, when I issue the query in an ssh terminal, I see the results
almost immediatly.
So although I should see the same latency over ssh , its way faster over ssh.
The transmitted data is small (the wireshard-file has 22kb, attached),
and even though the umts-network is high-latency its relativly high
bandwith (~512kbit/s up, ~

How to make panel automatically adjust to screen size?

Hi,

I have a laptop with a 1280x800 display, but when I'm at home I use an
external 1920x1200 monitor.
Is there any way to make my panel automatically adjust to the screen size?

With KDE-4.5.5 I got the following behaviour:
- Panel automatically resised when screen was too small (e.g. when I
started KDE after disabling the external monitor)
- Panel remained small, if it was smaller than screen.

With KDE-4.6 I get the following behaviour:
- Panel is no longer shrinked if panel-size > monitor.
This makes it quite uncomfortable to work with, e.g.

Howto access payload of notify?

Hi,

I would like to use the new feature of submitting payload with notify,
how can I access this data when listening with an jdbc client.

PGNotification seems to lack a getPayload() method.

Thank you in advance, Clemens

Client-Side triggers possible?

Hi,

Is there any way to get clients notified about data-changes without polling?

What I would need would be a client-side equivalent to triggers, e.g.
if one client inserts into a table all other interrested clients
should somehow get notified.

Thank you in advance, Clemens

Howto create bootable usb-stick without an ubuntu installation?

Hi,

I would like to install kubuntu on my laptop which doesn't have a
working CD drive.

I found a tutorial in the wiki which explains creating a bootable usb
stick using a program called "usb-creator", however its not available
on fedora, and is also missing on the lubuntu live-cd.

Is there a manual way to create a live usb stick?

Thank you in advance, Clemens

Boot usb live image, even if bios doesn't support it?

Hi,

I have a quite old laptop (2003) with a crappy bios, which doesn't
allow booting from USB and the laptop's dvd drive is broken.

Is there any way to write some bootloader-code on the HDD, which then
loads the live-cd from USB?

Thank you in advance, Clemens

Are Indices automatically generated for primary keys?

Hi,

Are indices for columns marked with "PRIMARY KEY" automatically generated by
postgresql, or do I have to do it manually?
The question might seem dumb, I ask because I remember from working with
MySQL it generates indices automatically in this case.

Thank you in advance, Clemens

Howto only select secific lines from a result?

Hi,

I am working on a graphical table display widget which should be able
to display huge amounts of data, by lazy-loading database values. It
already works well if the primary-key and line-number are equal.
However I don't have any idea howto handle the case where the
primary-key contains holes, caused e.g.

Howto script "sudo"?

Hello,

Is it possible to pass "sudo" the root-password in some way (I would
prefer plaintext)?

The reason is I use an umts-connection utility which has to run as
root, and I don't want to have my parents type a root-password every
time they connect to our ISP. For now I simply didn't set a
root-password, and choose "run as: root" in KDE, but I really dislike
this solution.

Thank you in advance, Clemens

Performance counters disabled in Fedora 13?

Hi,

When I tried sysprof on fedora-13 I only get a notification that
performance counters could not be opened.
Are performance counters turned off by default in Fedora 13, and if
so, how can I re-enable it?

Thank you in advance, Clemens

Grub-Menu takes ~30s to appear :/

Hi,

Since upgrading my old P4 based Laptop from Fedora-10 to Fedora-11 the
bootloader takes a very long time to start.
I later upgraded to Fedora 12 (because of improvements in the nouveau
driver) but that didn't help.
HDD is set to first boot device in BIOS.

It takes about ~30-60s for grub's menu to appear, everything else
works like expected.
I already re-installed grub successfully, but no change :/

Any idea what could be the problem?

Thank you in advance, Clemens

VirtualBox crashs system when starting VM

Hi,

Whenever I tried VirtualBox (even back in Fedora 11) it completly
locked up my machine as soon as powering up a VM.
I didn't care a lot, but now I am in trouble because I need it now and
VMware-Player refuses to install (waits forever in the
install-scripts) and VirtualBox crashes :/
I am now on Fedora-12 + updates testing, and I am using the VirtualBox
packages + kernel modules provided by Fedora/yum.

Any ideas what the problem could be?

In syslog I found this:

However at least 2.6.32.10 doesn't seem to provide perf_counter_paranoid :(

Thank you in advance, Clemens