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• 2 GB Should Be Enough For Me

  31 août 2010, par Multimedia Mike — General

  My new EeePC 1201PN netbook has 2 GB of RAM. Call me shortsighted but I feel like “that ought to be enough for me”. I’m not trying to claim that it ought to be enough for everyone. I am, however, questioning the utility of swap space for those skilled in the art of computing.

  
  
  Technology marches on : This ancient 128 MB RAM module is larger than my digital camera’s battery charger… and I just realized that comparison doesn’t make any sense
  

  Does anyone else have this issue ? It has gotten to the point where I deliberately disable swap partitions on Linux desktops I’m using ('swapoff -a'), and try not to allocate a swap partition during install time. I’m encountering Linux installers that seem to be making it tougher to do this, essentially pleading with you to create a swap partition– “Seriously, you might need 8 total gigabytes of virtual memory one day.” I’m of the opinion that if 2 GB of physical memory isn’t enough for my normal operation, I might need to re-examine my processes.

  In the course of my normal computer usage (which is definitely not normal by the standard of a normal computer user), swap space is just another way for the software to screw things up behind the scenes. In this case, the mistake is performance-related as the software makes poor decisions about what needs to be kept in RAM.

  And then there are the netbook-oriented Linux distributions that insisted upon setting aside as swap 1/2 gigabyte of the already constrained 4 gigabytes of my Eee PC 701′s on-board flash memory, never offering the choice to opt out of swap space during installation. Earmarking flash memory for swap space is generally regarded as exceptionally poor form. To be fair, I don’t know that SSD has been all that prevalent in netbooks since the very earliest units in the netbook epoch.

  Am I alone in this ? Does anyone else prefer to keep all of their memory physical in this day and age ?

• Révision 17466 : re-ecriture de la fonction d’upgrade des spip_auteurs_xxx en spip_auteurs_liens :

  22 mars 2011, par cedric -

  decoupe pour migrer une table a la fois

  generalisation pour etre utilisee pour n’importe quel autre pivot que auteur

  reduire la manipulation des donnees entre lecture et ecriture

  faire un delete par id_xxx, ce qui simplifie et reduit le nombre de requetes

  assurer l’avancement meme en cas de (...)

• Revisiting the Belco Alpha-400

  26 août 2010, par Multimedia Mike — General

  Relieved of the primary FATE maintenance duties, I decided to dust off my MIPS-based Belco Alpha-400 and try to get it doing FATE cycles. And just as I was about to get FATE running, I saw that Mans already got his MIPS-based Popcorn Hour device to run FATE. But here are my notes anyway.

  
  
  

  Getting A Prompt
  For my own benefit, I made a PDF to remind me precisely how to get a root prompt on the Alpha-400. The ‘jailbreak’ expression seems a little juvenile to me, but it seems to be in vogue right now.

  alpha-400-jailbreak.pdf

  Toolchain
  When I last tinkered with the Alpha-400, I was trying to build a toolchain that could build binaries to run on the unit’s MIPS chip, to no avail. Sometime last year, MichaelK put together x86_32-hosted toolchains that are able to build mipsel 32-bit binaries for Linux 2.4 and 2.6. The Alpha-400 uses a 2.4 kernel and the corresponding toolchain works famously for building current FFmpeg (--disable-devices is necessary for building).

  FATE Samples
  Next problem : Making the FATE suite available to the Alpha-400. I copied all of the FATE suite samples onto a VFAT-formatted SD card. The filename case is not preserved for all files which confounds me since it is preserved in other cases. I tried formatting the card for ext3 but the Alpha-400 would not mount it, even though /proc/filesystems lists ext3 (supporting an older version of ext3 ?).

  Alternative : Copy all of the FATE samples to the device’s rootfs. Space will be a little tight, though. Then again, there is over 600 MB of space free ; I misread earlier and thought there were only 300 MB free.

  Remote Execution
  To perform FATE cycles on a remote device, it helps to be able to SSH into that remote device. I don’t even want to know how complicated it would be to build OpenSSH for the device. However, the last time I brought up this topic, I learned about a lighter weight SSH replacement called Dropbear. It turns out that Dropbear runs great on this MIPS computer.

  Running FATE Remotely
  I thought all the pieces would be in place to run FATE at this point. However, there is one more issue : Running FATE on a remote system requires that the host and the target are sharing a filesystem somehow. My personal favorite remote filesystem method is sshfs which is supposed to work wherever there is an SSH server. That’s not entirely true, though– sshfs also requires sftp-server to be installed on the server side, a program that Dropbear does not currently provide.

  I’m not even going to think about getting Samba or NFS server software installed on the Alpha-400. According to the unit’s /proc/filesystems file, nfs is a supported filesystem. I hate setting up NFS but may see if I can get that working anyway.

  Residual Weirdness
  The unit comes with the venerable Busybox program (BusyBox v1.4.1 (2007-06-01 20:37:18 CST) multi-call binary) for most of its standard command line utilities. I noticed a quirk where BusyBox’s md5sum gives weird hex characters. This might be a known/fixed issue.

  Another item is that the Alpha-400′s /dev/null file only has rwxr-xr-x per default. This caused trouble when I first tried to scp using Dropbear using a newly-created, unprivileged user.