Scale Factor == Step Size

It could be the case, that in my own postings I referred to a ‘Scale Factor’, which would come prior to Quantization. In other works of reference, the term ‘Quantization Step’ might appear. As far as I am concerned, these terms are synonymous.

The goal could be to start with a maximum value as input, and to find a way to quantize it and all lower values, to arrive at a maximum quantized integer value. One would divide the (absolute) first by the second input value, to find this parameter, for an interval of time.

Dividing all the sample-values in the interval by the resulting parameter, will yield the maximum, quantized integer. And this parameter will also be equal to the minimum difference between the sample values, leading to two different quantized integers.

 

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Klystron has a Severe Issue, when Suspending.

In This Earlier Posting, I had written that my Linux laptop named ‘Klystron’ is able to suspend to RAM well and to Resume.

As it turns out, after lengthy experimentation, this was not true. What that system tends to do, after having woken up from Sleep, is to have its clock set ahead by 68 hours. This is a Known Bug. And although there is a script which has been suggested, and which I have gotten to run, which tries to repair this damage in a crude way, that script failed to do so in a complete way.

Even after I have set up This Script to run on Resume, after the first Suspend operation, everything seems to work again well. But after waking up for a second time, I found that the clock is set 136 hours ahead, instead of only being 68 hours ahead. And one reason fw this may happen, could be the fact that the script commands the system clock be set:

date -R --date="-68 hours ago"

This seems to have been a careless mistake, since to set the time to -68 Hours Ago, will actually set the time an additional 68 hours ahead. This can be verified, simply by running the above command from the command-line.

And so I have edited this script, into one which must be compliant with SystemD-based Suspend, instead of with Upstart-based Sleep and Hibernate, and my script needs to be placed into ‘/lib/systemd/system-sleep‘ in order even to get run. And here it is:

 


#!/bin/bash
#
# fixing https://bbs.archlinux.org/viewtopic.php?id=173487

case "$1" in
  pre)
    date +%s > /tmp/suspend.log
    ;;
  post)
    was=`cat /tmp/suspend.log`
    now=`date +%s`
    # time shifts for 68 hours
    if [ $now -gt `expr $was + 244800` ]; then
      date -s "`date -R --date="68 hours ago"`"
    fi
    /etc/init.d/nmbd restart
    ;;
  *)
    ;;
esac

 

The simple fact that my networking client could be connecting to the network, with false time information, can ‘discredit’ my client in the computerized mind of the router or server. And when a LAN client etc. is discredited, this can lead to connection problems…

For now, I am going to experiment further with trying to correct this. But if I run into further problems with this project, I am likely to abandon it.

Dirk

 

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One main reason for Choosing Kanotix

A question which many people have asked me, was ‘What is the advantage of choosing Kanotix, over choosing just any generic Debian / Linux OS?’

And an important area in Linux, is hardware recognition. We tend to appreciate it, if we can install a Linux system with little or no mess. And Kanotix users are of the variety, who want to be able to plug in all the latest hardware, and just have it play.

Kanotix does not always ship with the generic, stock Debian kernel, but with a special Kanotix kernel build, that has all the latest drivers in-tree. And it is a bit of a joke which we sometimes make, that even though Windows introduced the concept first, in many cases, Linux can be more plug-and-play than Windows is.

This is especially true for Kanotix.

Dirk

 

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Progress with the WiFi on Klystron

In This Earlier Posting, I had written that there were once stability issues, with the WiFi chip-set of my laptop, which I name ‘Klystron’.

Since then, there has been some updating of the kernel, and therefore also some updating of the in-tree kernel module, which operates the WiFi chip-set, and some updating of the firmware as well.

The way the behavior of the laptop has been since then is, that its WiFi connection finally seems stable, at 802.11n speeds and with H/W encryption, but that a rather odd behavior has cropped up, according to which the membership of that laptop in my Samba Workgroup, seems to fail overnight, consistently.

What I seem to decipher, is that this later malfunction is related to the fact that, like many Linux systems, ‘Klystron’ restarts some of its services periodically – nightly – including the ‘nmbd‘ Daemon, the Linux equivalent of the ‘Network Monitoring BIOS Daemon’, which emulates ‘NetBIOS‘. And something about the way the restart takes place is still not perfectly kosher. It seems to require I disconnect from the WiFi afterward, and simply reconnect, before the local laptop shows up as part of my Workgroup again. And yet, it remains fully possible to surf the Web, as well as just to connect directly to my Samba server and to browse it, using a predefined IP address…

But for the moment, there is no reason to suspect, that this has anything at all to do with the Firmware or the Kernel Module. And it has taken me some period of observation to reach that conclusion.

Dirk

 

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