How do I increase the size of logcat buffers?
To find out the actual size of the ring buffer, you can use

$ adb logcat -g


To adjust the size of the ring buffer, you might try

$ adb logcat -r &lt;kbytes&gt;


At least that's what some tutorials say. For more details, you might want to read "adb logcat" Command Options and Log Buffers.

P.S.: I guess those settings (manual adjusted ring buffer size) will not survive a reboot -- just to consider.