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memory_usage [2008/07/28 05:14] (current)
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 +======The client uses too much memory=====
 +If you think the client is using too much memory, you may think there is a
 +memory leak.  But before you report a bug, consider the following common ​
 +causes of high memory usage, and ways to reduce usage.
 +
 +* A window that is in scrollback mode does not trim its scrollback -- it will grow without any limit. ​ A busy channel can use a lot of memory in a couple of days if you forget you're in scrollback.
 +* A window that has an extremely large scrollback (10,000 lines). ​ Each scrollback entry holds one physical line of display, which might average about 40 characters, so that's up to 400k **per window**.
 +* A window that has an extremely large lastlog (5,000 lines). ​ Each lastlog entry holds one logical line iof display, which can be of any size.  An average size might be about 50 characters, so that's up to 250k **per window**.
 +* A lot of windows are open.  Even if the lastlog and scrollback sizes are modest, if you have a lot of windows open (over 20), it can add up fast.
 +* A lot of aliases and assigns. ​ Your script has to be loaded into memory as a text file, and is pretty much stored as text.  So if your script is 150k, the client will grow by at least that much.
 +* A lot of channels. ​ The client keeps track of every channel you are on, and the nicknames of all of the people on those channels, and their userhosts. ​ A channel with 50 people would take about 5k of memory. ​ If you're joining 100 channels on 12 servers...
 +* A lot of servers. ​ An entry in the server list takes about 16k of memory.
 +
 +Unfortunately,​ reducing memory usage will not usually reduce the amount
 +of memory reported in '​top'​ or '​ps'​ because in most unix libc'​s,​ malloc()ed ​
 +memory that is free()d is saved for re-use and is not returned to the
 +operating system. ​ But that is not so bad, because the operating system ​
 +is smart, and memory that is allocated but unused will be paged out.
 +
  
memory_usage.txt ยท Last modified: 2008/07/28 05:14 (external edit)