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  14  <h1>
  15      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  16
  17  </h1>
  18
  19 </div>
  20
  21
  22     <h3>Entries from April 2012.</h3>
  23
  24     <div class="entry">
  25       <div class="title">
  26         <a href="http://people.skolelinux.org/pere/blog/Debian_Edu_interview__Wolfgang_Schweer.html">Debian Edu interview: Wolfgang Schweer</a>
  27       </div>
  28       <div class="date">
  29          1st April 2012
  30       </div>
  31       <div class="body">
  32         <p>Germany is a core area for the
  33 <a href="http://www.skolelinux.org/">Debian Edu and Skolelinux</a>
  34 user community, and this time I managed to get hold of Wolfgang
  35 Schweer, a valuable contributor to the project from Germany.
  36
  37 <p><strong>Who are you, and how do you spend your days?</strong></p>
  38
  39 <p>I've studied Mathematics at the university 'Ruhr-Universität' in
  40 Bochum, Germany. Since 1981 I'm working as a teacher at the school
  41 "<a href="http://www.westfalenkolleg-dortmund.de/">Westfalen-Kolleg
  42 Dortmund</a>", a second chance school.  Here, young adults is given
  43 the opportunity to get further education in order to do the school
  44 examination 'Abitur', which will allow to study at a university. This
  45 second chance is of value for those who want a better job perspective
  46 or failed to get a higher school examination being teens.</p>
  47
  48 <p>Besides teaching I was involved in developing online courses for a
  49 blended learning project called 'abitur-online.nrw' and in some other
  50 information technology related projects. For about ten years I've been
  51 teacher and coordinator for the 'abitur-online' project at my
  52 school. Being now in my early sixties, I've decided to leave school at
  53 the end of April this year.</p>
  54
  55 <p><strong>How did you get in contact with the Skolelinux/Debian Edu
  56 project?</strong></p>
  57
  58 <p>The first information about Skolelinux must have come to my
  59 attention years ago and somehow related to LTSP (Linux Terminal Server
  60 Project).  At school, we had set up a network at the beginning of 1997
  61 using Suse Linux on the desktop, replacing a Novell network. Since
  62 2002, we used old machines from the city council of Dortmund as thin
  63 clients (LTSP, later Ubuntu/Lessdisks) cause new hardware was out of
  64 reach. At home I'm using Debian since years and - subscribed to the
  65 Debian news letter - heard from time to time about Skolelinux. About
  66 two years ago I proposed to replace the (somehow undocumented and only
  67 known to me) system at school by a well known Debian based system:
  68 Skolelinux.</p>
  69
  70 <p>Students and teachers appreciated the new system because of a
  71 better look and feel and an enhanced access to local media on thin
  72 clients.  The possibility to alter and/or reset passwords using a GUI
  73 was welcomed, too. Being able to do administrative tasks using a GUI
  74 and to easily set up workstations using PXE was of very high value for
  75 the admin teachers.</p>
  76
  77 <p><strong>What do you see as the advantages of Skolelinux/Debian
  78 Edu?</strong></p>
  79
  80 <p>It's open source, easy to set up, stable and flexible due to it's
  81 Debian base. It integrates LTSP out-of-the-box. And it is documented!
  82 So it was a perfect choice.</p>
  83
  84 <p>Being open source, there are no license problems and so it's
  85 possible to point teachers and students to programs like
  86 OpenOffice.org, ViewYourMind (mind mapping) and The Gimp.  It's of
  87 high value to be able to adapt parts of the system to special needs of
  88 a school and to choose where to get support for this.</p>
  89
  90 <p><strong>What do you see as the disadvantages of Skolelinux/Debian
  91 Edu?</strong></p>
  92
  93 <p>Nothing yet.</p>
  94
  95 <p><strong>Which free software do you use daily?</strong></p>
  96
  97 <p>At home (Debian Sid with Gnome Desktop): Iceweasel, LibreOffice,
  98 Mutt, Gedit, Document Viewer, Midnight Commander, flpsed (PDF
  99 Annotator).  At school (Skolelinux Lenny): Iceweasel, Gedit,
 100 LibreOffice.</p>
 101
 102 <p><strong>Which strategy do you believe is the right one to use to
 103 get schools to use free software?</strong></p>
 104
 105 <p>Some time ago I thought it was enough to tell people about it. But
 106 that doesn't seem to work quite well. Now I concentrate on those more
 107 interested and hope to get multiplicators that way.</p>
 108
 109       </div>
 110       <div class="tags">
 111
 112
 113         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju</a>.
 114
 115
 116       </div>
 117     </div>
 118     <div class="padding"></div>
 119
 120     <div class="entry">
 121       <div class="title">
 122         <a href="http://people.skolelinux.org/pere/blog/Debian_Edu_in_the_Linux_Weekly_News.html">Debian Edu in the Linux Weekly News</a>
 123       </div>
 124       <div class="date">
 125          5th April 2012
 126       </div>
 127       <div class="body">
 128         <p>About two weeks ago, I was interviewed via email about
 129 <a href="http://www.skolelinux.org/">Debian Edu and Skolelinux</a> by
 130 Bruce Byfield in Linux Weekly News.  The result was made public for
 131 non-subscribers today.  I am pleased to see liked our Linux solution
 132 for schools.  Check out his article
 133 <a href="https://lwn.net/Articles/488805/">Debian Edu/Skolelinux: A
 134 distribution for education</a> if you want to learn more.</p>
 135
 136       </div>
 137       <div class="tags">
 138
 139
 140         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 141
 142
 143       </div>
 144     </div>
 145     <div class="padding"></div>
 146
 147     <div class="entry">
 148       <div class="title">
 149         <a href="http://people.skolelinux.org/pere/blog/Why_the_KDE_menu_is_slow_when__usr__is_NFS_mounted___and_a_workaround.html">Why the KDE menu is slow when /usr/ is NFS mounted - and a workaround</a>
 150       </div>
 151       <div class="date">
 152          6th April 2012
 153       </div>
 154       <div class="body">
 155         <p>Recently I have spent time with
 156 <a href="http://www.slxdrift.no/">Skolelinux Drift AS</a> on speeding
 157 up a <a href="http://www.skolelinux.org/">Debian Edu / Skolelinux</a>
 158 Lenny installation using LTSP diskless workstations, and in the
 159 process I discovered something very surprising.  The reason the KDE
 160 menu was responding slow when using it for the first time, was mostly
 161 due to the way KDE find application icons.  I discovered that showing
 162 the Multimedia menu would cause more than 20 000 IP packages to be
 163 passed between the LTSP client and the NFS server.  Most of these were
 164
 165 NFS LOOKUP calls, resulting in a NFS3ERR_NOENT response.  Because the
 166 ping times between the client and the server were in the range 2-20
 167 ms, the menus would be very slow.  Looking at the strace of kicker in
 168 Lenny (or plasma-desktop i Squeeze - same problem there), I see that
 169 the source of these NFS calls are access(2) system calls for
 170 non-existing files.  KDE can do hundreds of access(2) calls to find
 171 one icon file.  In my example, just finding the mplayer icon required
 172 around 230 access(2) calls.</p>
 173
 174 <p>The KDE code seem to search for icons using a list of icon
 175 directories, and the list of possible directories is large.  In
 176 (almost) each directory, it look for files ending in .png, .svgz, .svg
 177 and .xpm.  The result is a very slow KDE menu when /usr/ is NFS
 178 mounted.  Showing a single sub menu may result in thousands of NFS
 179 requests.  I am not the first one to discover this.  I found a
 180 <a href="https://bugs.kde.org/show_bug.cgi?id=211416">KDE bug report
 181 from 2009</a> about this problem, and it is still unsolved.</p>
 182
 183 <p>My solution to speed up the KDE menu was to create a package
 184 kde-icon-cache that upon installation will look at all .desktop files
 185 used to generate the KDE menu, find their icons, search the icon paths
 186 for the file that KDE will end up finding at run time, and copying the
 187 icon file to /var/lib/kde-icon-cache/.  Finally, I add symlinks to
 188 these icon files in one of the first directories where KDE will look
 189 for them.  This cut down the number of file accesses required to find
 190 one icon from several hundred to less than 5, and make the KDE menu
 191 almost instantaneous.  I'm not quite sure where to make the package
 192 publicly available, so for now it is only available on request.</p>
 193
 194 <p>The bug report mention that this do not only affect the KDE menu
 195 and icon handling, but also the login process.  Not quite sure how to
 196 speed up that part without replacing NFS with for example NBD, and
 197 that is not really an option at the moment.</p>
 198
 199 <p>If you got feedback on this issue, please let us know on debian-edu
 200 (at) lists.debian.org.</p>
 201
 202       </div>
 203       <div class="tags">
 204
 205
 206         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 207
 208
 209       </div>
 210     </div>
 211     <div class="padding"></div>
 212
 213     <p style="text-align: right;"><a href="04.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14" /></a></p>
 214     <div id="sidebar">
 215
 216
 217
 218 <h2>Archive</h2>
 219 <ul>
 220
 221 <li>2012
 222 <ul>
 223
 224 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 225
 226 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 227
 228 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 229
 230 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (3)</a></li>
 231
 232 </ul></li>
 233
 234 <li>2011
 235 <ul>
 236
 237 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 238
 239 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 240
 241 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 242
 243 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 244
 245 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 246
 247 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 248
 249 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 250
 251 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 252
 253 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 254
 255 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 256
 257 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
 258
 259 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
 260
 261 </ul></li>
 262
 263 <li>2010
 264 <ul>
 265
 266 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 267
 268 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 269
 270 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 271
 272 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 273
 274 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 275
 276 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 277
 278 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 279
 280 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
 281
 282 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
 283
 284 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
 285
 286 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
 287
 288 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
 289
 290 </ul></li>
 291
 292 <li>2009
 293 <ul>
 294
 295 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 296
 297 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 298
 299 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 300
 301 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 302
 303 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 304
 305 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 306
 307 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 308
 309 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 310
 311 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 312
 313 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 314
 315 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 316
 317 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 318
 319 </ul></li>
 320
 321 <li>2008
 322 <ul>
 323
 324 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 325
 326 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 327
 328 </ul></li>
 329
 330 </ul>
 331
 332
 333
 334 <h2>Tags</h2>
 335 <ul>
 336
 337  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
 338
 339  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 340
 341  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 342
 343  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (2)</a></li>
 344
 345  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (12)</a></li>
 346
 347  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
 348
 349  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (54)</a></li>
 350
 351  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (96)</a></li>
 352
 353  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (7)</a></li>
 354
 355  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (120)</a></li>
 356
 357  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (15)</a></li>
 358
 359  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
 360
 361  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (21)</a></li>
 362
 363  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (15)</a></li>
 364
 365  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (8)</a></li>
 366
 367  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (4)</a></li>
 368
 369  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 370
 371  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (14)</a></li>
 372
 373  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (156)</a></li>
 374
 375  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (120)</a></li>
 376
 377  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
 378
 379  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (24)</a></li>
 380
 381  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (46)</a></li>
 382
 383  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
 384
 385  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
 386
 387  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (2)</a></li>
 388
 389  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (4)</a></li>
 390
 391  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 392
 393  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
 394
 395  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (23)</a></li>
 396
 397  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
 398
 399  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (24)</a></li>
 400
 401  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (1)</a></li>
 402
 403  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (3)</a></li>
 404
 405  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (9)</a></li>
 406
 407  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (6)</a></li>
 408
 409  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (23)</a></li>
 410
 411  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (1)</a></li>
 412
 413  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (18)</a></li>
 414
 415 </ul>
 416
 417
 418     </div>
 419     <p style="text-align: right">
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