December 2012 - Roundtable

linux not caching files very long
by Trevor Cordes 05 Dec '12

05 Dec '12

My main box has 8GB RAM. There's usually 3GB of programs running. The rest usually is shown as free or going to buffers/cache. I have a set of files I often linearly scan through and they are around 1GB. They used to read in and stay cached for hours (I can tell because my scan takes 3s when cached and 90s when not!). Now they seem to get dropped and require re-reading all the time, like if I don't use them for a few minutes. AFAICT my ps load has not changed and I'm not doing anything that is requiring more cache/buffers that is pushing them out. This seems to have started when I upgraded my kernel from 3.4 to 3.6 (Fedora 16) though I can't be sure at this point. Does anyone know of some tunables I can try to tell the kernel to be more likely to cache for longer? I'd rather cache at the expense of pushing more programs to swap (I run a zillion programs at all times and never close them). I have played with /proc/sys/vm/swappiness (80 has been great for me in the past) but a) it doesn't seem to affect my problem now, and b) the docs leave me scratching my head about how it really affects file caching. At this point I'm not interested in solutions that are "rethink your scan!" as I do plan to one day database-itize and index the 1GB data set... but not today!

2 4

RaspBerry Pi for sale locally!
by Dan Keizer 05 Dec '12

05 Dec '12

Well, I didn't believe my eyes when I saw it ! I was in Active Electronics on Century in St. James picking up some RF adapters when I spotted a name brand that I recognized on the for sale table up front ... "Newark Element 14" ... Looking more closely at them they are the latest Raspberry PI's! I believe they were selling for $49 ... at that price, they will be gone soon, so pick them up while you can... :-) Dan.

2 1

MUUG Meeting, Dec 11, 7:30pm -- Round-table, Mingling and Munchies
by gedetil＠cs.umanitoba.ca 04 Dec '12

04 Dec '12

The Manitoba UNIX User Group (MUUG) will be holding its next monthly meeting on Tuesday, December 11. The meeting topic for this month is as follows: Round-table, Mingling and Munchies Instead of a formal presentation this month, we will be starting the holiday season with an informal round-table meeting at a restaurant. We are leaving our normal meeting place at the IBM offices, and will be meeting at the Seine River Café. The Seine River Café is located at 390 Provencher Blvd, just east of Des Meurons. We will be meeting for dinner at 6:00 pm. Please email us to let us know how many people will be attending, so we have an idea of how much space to reserve with the restaurant. Brad Vokey will be collecting the RSVPs, so check out the MUUG web site for details on how to contact Brad. If you can't make it for dinner, drop by at 7:30 for an informal roundtable and social meeting - a great chance to chat with other MUUG attendees and to celebrate the holiday season. MUUG will be providing a few light refreshments; you can order more food and drink from the restaurant if you like. Winnipeg Harvest Food Drive As we have done in previous years, we are collecting non-perishable food items for Winnipeg Harvest. Please bring a non-perishable food to the December restaurant meeting to drop in our box. Winnipeg Harvest lists their most wanted food items here: http://winnipegharvest.org/10-most-wanted-food-items/ The group holds its general meetings at 7:30pm on the second Tuesday of every month from September to June. (There are no meetings in July and August.) Meetings are open to the general public; you don't have to be a MUUG member to attend. For more information about MUUG, and its monthly meetings, check out their Web server: http://www.muug.mb.ca/ Help us promote this month's meeting, by putting this poster up on your workplace bulletin board or other suitable public message board: http://www.muug.mb.ca/meetings/MUUGmeeting.pdf -- Gilbert E. Detillieux E-mail: <gedetil(a)muug.mb.ca> Manitoba UNIX User Group Web: http://www.muug.mb.ca/ PO Box 130 St-Boniface Phone: (204)474-8161 Winnipeg MB CANADA R2H 3B4 Fax: (204)474-7609

1 0

Re: [RndTbl] Screwdriver
by Adam Thompson 03 Dec '12

03 Dec '12

Princess Auto sells several security-bit sets, I believe at least two of them include the triangle bits. -Adam Kevin McGregor <kevin.a.mcgregor(a)gmail.com> wrote: >_______________________________________________ >Roundtable mailing list >Roundtable(a)muug.mb.ca >http://www.muug.mb.ca/mailman/listinfo/roundtable

3 2

Screwdriver
by Kevin McGregor 02 Dec '12

02 Dec '12

Does anyone have, or know where I can get, a small triangle-head screwdriver? I have a long (150-bulb) Christmas tree light set that doesn't work at all. It has a controller to make the lights do different flashy things, and the controller seems to be held together with two screws with triangle-shaped sockets. Not Robertson, not Tor-x. The whole thing worked fine last year, and I'd like to have it working again. I thought I would take it apart to see if there was anything obviously wrong with it (check for voltages, etc.).

3 2