Django optimisation in production

Few days ago I realised that my django installation in production started producing too many memory errors - thanks to monit memory alerts were filling my mailbox without any serious service interruption. But hundreds email messages daily annoyed me enough to look deeper into trouble.

1) I switched on django debug ...

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Secure Riak installation using n2n VPN

Recently, I decided to have a closer look at Riak non-sql database, but found out that unlike CouchDB riak doesn't have a HTTP basic auth implemented, or any other way of defining secure access to database.

I have three servers to build a cluster, but I feel very uneasy ...

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Useful JavaScript one-liner for couchdb

I found myself using more and more of this one-liner for working with couchdb database:

var getNewDatabusUUID = JSON.parse($.ajax({ type: "GET", url: "/_uuids/",                async: false }).responseText);  $.log("New uuid generated " + getNewDatabusUUID.uuids);

this example retrieves new uuids from couchdb, but I was using it to retrieve _rev of the ...

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Amazing examples of misuse of data mining in finance

From stupid Data Mining Tricks: Overfitting S&P 500:

"Norman Bloom, no doubt a champion of all data miners, went beyond trying to predict the stock market. Instead, he used the stock market, along with baseball scores, particularly those involving the New York Yankees, to “read the mind of God ...

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Wordpress deployment on the live server using chef (and vagrant)

When I decided to move from movable type to wordpress, I wasn't quite happy with default wordpress cookbook. I also had an offer to have a cheap dedicated server instead of VPS, so I decided to test two things simultaneously:

* Preparation of new live server using fabric

* Deployment of ...

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Movable type replacement: wordpress, jekill or Golbarg?

I am a bit fed up with MT, I looked at MT5 and as usual was seriously annoyed by MT backup behavior: I attempted to recover backup from mt 4 into clean mt 5 and hit usual wall with schema mismatch error. I believe recovery should work, no matter what ...

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Test of latex plugin, Pareto front definition

Definition: We say that a vector of decision variables $ \hat x^{*} \in F$ is Pareto optimal if there does not exist another $ \hat x \in F$ such that $ f(\hat x) \le f(\hat x^{*})$ for all $ i = 1, \hdots k $ and $ f_{j}(\hat x)< f_{j}(\hat x ...

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Building nginx on ubuntu karmic

Building nginx on ubuntu

sudo aptitude -R install build-essential libpcre3 libpcre3-dev libpcrecpp0 libssl-dev zlib1g-dev

./configure --prefix=/etc/nginx \--sbin-path=/usr/sbin/nginx \--conf-path=/etc/nginx/nginx.conf \--error-log-path=/var/log/nginx/error.log \--pid-path=/var/run/nginx.pid \--lock-path=/var/lock/nginx.lock \--user=www-data \--group=www-data \--http-log-path=/var/log ...

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Cloud computing security, common questions and my answers

I have a several friends, who have a great product ideas, based on complex scientific algorithms. Each time when I suggest using cloud computing for developing product we go through a round of questions. I will put them down here, so I can reference it.

If you want to make ...

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Mysql DB and unicode utf8

Do you expect newest Ubuntu server 9.10 (karmic) to support utf8 in mysql server out of the box? Well, it doesn't.

Don't forget to put small file */etc/mysql/conf.d/charset.cnf*:

[mysqld]

character-set-server=utf8

default-collation=utf8_unicode_ci

character_set_client=utf8

[mysql]

default-character-set=utf8

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