SEARCH KEYWORD -- SLOW QUERY

  One reason why mcrypt responds slowly

This morning one colleague came over and talked about one script which used mcrypt responded very slowly, the server configurations are fine. But the reason for the slowness is unknown. Here is one script which reproduces the issue: <?php $dmcryptText = "dummy"; $key = "foobar"; $size = mcrypt_get_iv_size(MCRYPT_BLOWFISH,MCRYPT_MODE_ECB); $iv = mcrypt_create_iv($size); //Take care $m = mcrypt_ecb(MCRYPT_BLOWFISH, $key, $dmcryptText, MCRYPT_DECRYPT, $iv); var_dump($m); When 20 requests of&...

   SOLUTION,SLOW,MCRYPT,RESPONSE,PHP     2012-09-27 12:03:16

  Bytes Matter

I love to profile applications, because I always learn something that surprises me. Initial Profiler Surprise: Client Side Case in point, I was recently profiling our Android application, the Famigo Sandbox. This app sends a lot of data back and forth with our API, as we try to determine which of the apps on your phone are safe for your kids. I always assumed that, if app performance suffered during some of the ...

   Byte,Low level,Operation,Importance     2012-02-28 08:07:22

  Why I love everything you hate about Java

If you’re one of those hipster programmers who loves Clojure, Ruby, Scala, Erlang, or whatever, you probably deeply loathe Java and all of its giant configuration files and bloated APIs of AbstractFactoryFactoryInterfaces. I used to hate all that stuff too. But you know what? After working for all these months on these huge pieces of Twitter infrastructure I’ve started to love the AbstractFactoryFactories. Let me explain why. Consider this little Scala program. It uses â€Å...

   Java,Comparison,Modularity,API     2011-11-29 08:48:15

  OpenLDAP Proxy -- rwm-map vs map

OpenLDAP proxy is used to proxy ldap request and response between clients and servers, different servers may have different representations/attributes to mean the same thing. For example, in one LDAP server, the firstName may be represented by firstName, it may be represented by givenName in a different server. However, from the client perspective, it only wants to get the firstName, it doesn't care about the backend attributes. In this case, attribute mapping can help provide a virtual view of ...

   MAP,OPENLDAP,OPENLDAP PROXY,LDAP,RWM-MAP     2018-02-02 20:36:02

  gethostbyname vs getaddrinfo

getaddrinfo is slower than ping when resolving domain names. I think ping uses gethostbyname to resolve a domain name. The question becomes whether getaddrinfo is slower than gethostbyname. After testing with both functions, we find that getaddrinfo is really slow compared to gethostbyname. By strace tracking,  we find getaddrinfo will communicate with DNS server 10 times and gethostbyname will communicate with DNS server communication twice.gethostbyname is an old way to resolve domain nam...

   C++,network,DNS     2012-08-15 14:06:34

  Create Packed Indexes with MySQL

I am pretty much sure that you are aware of indexes which we are creating on database fields. Indexes are very useful to make your query search faster and improve the site performance. But the fact is that Indexes which we are creating on database tables also require some additional space on your hard disk and if you have not properly created these indexes than some t...

   MySQL,Compressed index,PACK_KEYS     2012-04-24 07:42:18

  OpenLDAP Proxy -- slapd.conf

In the introductory post of OpenLDAP proxy, we mentioned that slapd.conf is the configuration file which tells the slapd service what to do.  Apart from this, there is a dynamic way of configuring slapd where the configurations are stored in LDIF database. In the future, LDIF database will be the one for configuring slapd, the old style of slapd.conf is deprecated. The slapd.conf can be converted to LDIF style using the slapdtest command. slapdtest -f /etc/ldap/slapd.conf -F /etc...

   OPENLDAP,OPENLDAP PROXY,SLAPD,SLAPD.CONF     2017-10-29 04:01:39

  Inline IF and CASE statements in MySQL

There are times where running IF statements inside a query can be useful. MySQL provides a simple way to do this through the use of IF and CASE statements. The IF statement takes three arguments; the conditional, the true value and the false value. False and true values may be static values or column values. For example: SELECT IF(score > 100, 100, score) AS score FROM exam_results this will return the value in the score column limited to a maximum value of 100. IF statements can a...

   MySQK,IF,Condition,CASE,SQL     2012-04-22 10:37:01

  CSS box-shadow Can Slow Down Scrolling

Working on one of the Chromebooks Google lets you borrow on Virgin America flights, I noticed scrolling down the page on my airbnb.com dashboard was much slower than on my normal laptop. I chalked it up to weak Chromebook hardware, but other sites were scrolling just fine. box-shadow had caused slow scrolling on our search results page before, so I did some investigation.I used Chrome's Timeline tab to see the duration of paint events on the page. Before each test I forced a garbage collection a...

   CSS,box-shadow,performance,Timeline,Chromebook     2011-11-13 08:13:48

  Using C for a specialized data store

Pixenomics stores and transports 1.2 million pixels from the server to the client. During development we played with various methods to store and process this. Our ultimate goal was to send the entire board in under 1 second. During the stages of prototyping we used a MySQL database without thinking too much about performance. With a mere 2,000 pixels we quickly realised this wasn’t even usable as a demo. Changing the storage engine to memory was much better but still obviously unu...

   C,Data store,Efficiency,Performance     2012-03-07 05:09:38

RECENT