| Andrew Cooke | Contents | Latest | RSS | Twitter | Previous | Next


Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

C-ORM: docs, API.

Last 100 entries

Small Success With Go!; Re: Quick message - This link is broken; Adding Reverb To The Echo Chamber; Sox Audio Tools; Would This Have Been OK?; Honesty only important economically before institutions develop; Stegangraphy via PS4; OpenCL Mess; More Book Recommendations; Good Explanation of Difference Between Majority + Minority; Musical Chairs - Who's The Privileged White Guy; I can see straight men watching this conversation and laffing; When it's Actually a Source of Indignation and Disgust; Meta Thread Defending POC Causes POC To Close Account; Indigenous People Of Chile; Curry Recipe; Interesting Link On Marginality; A Nuclear Launch Ordered, 1962; More Book Recs (Better Person); It's Nuanced, And I Tried, So Back Off; Marx; The Negative Of Positive; Jenny Holzer Rocks; Huge Article on Cultural Evolution and More; "Ignoring language theory"; Negative Finger Counting; Week 12; Communication Via Telecomm Bids; Finding Suspects Via Relatives' DNA From Non-Crime Databases; Statistics and Information Theory; Ice OK in USA; On The Other Hand; (Current Understanding Of) Chilean Taxes / Contributions; M John Harrison; Playing Games on a Cloud GPU; China Gamifies Real Life; Can't Help Thinking It's Thoughtcrime; Mefi Quotes; Spray Painting Bike Frame; Weeks 10 + 11; Change: No Longer Possible To Merge Metadata; Books on Old Age; Health Tree Maps; MRA - Men's Rights Activists; Writing Good C++14; Risk Assessment - Fukushima; The Future of Advertising and Surveillance; Travelling With Betaferon; I think I know what I dislike so much about Metafilter; Weeks 8 + 9; More; Pastamore - Bad Italian in Vitacura; History Books; Iraq + The (UK) Governing Elite; Answering Some Hard Questions; Pinochet: The Dictator's Shadow; An Outsider's Guide To Julia Packages; Nobody gives a shit; Lepton Decay Irregularity; An Easier Way; Julia's BinDeps (aka How To Install Cairo); Good Example Of Good Police Work (And Anonymity Being Hard); Best Santiago Burgers; Also; Michael Emmerich (Vibrator Translator) Interview (Japanese Books); Clarice Lispector (Brazillian Writer); Books On Evolution; Looks like Ara (Modular Phone) is dead; Index - Translations From Chile; More Emotion in Chilean Wines; Week 7; Aeon Magazine (Science-ish); QM, Deutsch, Constructor Theory; Interesting Talk Transcripts; Interesting Suggestion Of Election Fraud; "Hard" Books; Articles or Papers on depolarizing the US; Textbook for "QM as complex probabilities"; SFO Get Libor Trader (14 years); Why Are There Still So Many Jobs?; Navier Stokes Incomplete; More on Benford; FBI Claimed Vandalism; Architectural Tessellation; Also: Go, Blake's 7; Delusions of Gender (book); Crypto AG DID work with NSA / GCHQ; UNUMS (Universal Number Format); MOOCs (Massive Open Online Courses); Interesting Looking Game; Euler's Theorem for Polynomials; Weeks 3-6; Reddit Comment; Differential Cryptanalysis For Dummies; Japanese Graphic Design; Books To Be Re-Read; And Today I Learned Bugs Need Clear Examples; Factoring a 67 bit prime in your head; Islamic Geometric Art; Useful Julia Backtraces from Tasks; Nothing, however, is lost with less discomfort than that which, when lost, cannot be missed

© 2006-2015 Andrew Cooke (site) / post authors (content).

Low Latency(?) Kernel for OpenSuse 11.1

From: "andrew cooke" <andrew@...>

Date: Fri, 30 Jan 2009 21:11:39 -0300 (CLST)

I did the following to compile a low latency kernel for Opensuse 11.1.  In
truth I don't fully understand the options, so I may not have chose things
correctly.  In any case, my audio playback still has intermittent hiccups,
so I will return to the default kernel (since it's simpler to maintain).

But in case it's helpful for anyone else, this is what I did.  Basically
just install the kernel source and follow the instructions in the README -
/usr/share/doc/packages/kernel-source/README.SUSE.  This link is also
useful -

- Check that current system is up-to-date via Yast (all
  packages; update if newer version available)

- Install the kernel-source package

- Make a copy of boot/grub/menu.lst

- Note info from boot.msg:
  root=/dev/md3 resume=/dev/md5 splash=silent showopts vga=0x31a

- Note the location of /boot:
  Device: /dev/sdd1
  Device Path: pci-0000:00:1f.2-scsi-0:0:1:0-part1
  Device ID 1: ata-WDC_WD3200JS-60PDB0_WD-WCAPD2606109-part1
  Device ID 2: scsi-SATA_WDC_WD3200JS-60_WD-WCAPD2606109-part1

- Read .boot/boot.readme and noted:
p6 boot: cat /boot/grub/device.map
(hd1)   /dev/disk/by-id/ata-WDC_WD3200JS-60PDB0_WD-WCAPD2606109
(hd5)   /dev/disk/by-id/scsi-SFUJITSU_MAN3184MP_UFS0P1900J1C
(hd0)   /dev/disk/by-id/ata-WDC_WD3200JS-60PDB0_WD-WCAPD2611078
(hd3)   /dev/disk/by-id/ata-WDC_WD3200JS-60PDB0_WD-WCAPD2661401
(hd4)   /dev/disk/by-id/scsi-SFUJITSU_MAN3184MP_UFS0P1900D0N
(hd2)   /dev/disk/by-id/ata-WDC_WD3200JS-60PDB0_WD-WCAPD2606397
qp6 boot: cat /etc/grub.conf
setup --stage2=/boot/grub/stage2 --force-lba (hd0) (hd1,0)

- It's not clear to me where the boot loader is installed.
  The Yast boot loader config gives MBR as the boot loader
  location defeault.

- Read /usr/share/doc/packages/kernel-source/README.SUSE

- cd /usr/src/linux

- make cloneconfig

- more Makefile; make help

- make xconfig
  (failed; install qt3-devel; retry)
  Disable dynamic ticks
  Select correct processor family
  Select preemptible kernel
  Set time frequency to 1000Hz
  Can see no way to set localversion.

- make menuconfig
  Set Local version

- make
  make modules_install
  make install

- egrep allow_unsupported_modules /etc/modprobe.d/unsupported-modules
  (shows 1)

- check /boot/grub/menu.lst
  check /boot

- reboot

- no X11

- init 3
  cd /usr/share/doc
  mkdir nvidia
  cd nvidia
  chmod +x NVIDIA-Linux-x86_64-180.22-pkg2.run

- reboot


Only Early Kernels

From: "andrew cooke" <andrew@...>

Date: Tue, 30 Jun 2009 19:10:12 -0400 (CLT)

I should add (since this page gets occasional readers) that this was only
a problem with early kernels in OpenSuse 11.1.  If you update via Yast
then you should get a kernel with no latency issues (ie it plays back
music just fine).


Comment on this post