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Chris Down 8806b6e237 manage: propertynotify: Reduce cost of unused size hints
This patch defers all size hint calculations until they are actually
needed, drastically reducing the number of calls to updatesizehints(),
which can be expensive when called repeatedly (as it currently is during
resizes).

In my unscientific testing this reduces calls to updatesizehints() by
over 90% during a typical work session. There are no functional changes
for users other than an increase in responsiveness after resizes and
a reduction in CPU time.

In slower environments or X servers, this patch also offers an
improvement in responsiveness that is often tangible after resizing a
client that changes hints during resizes.

There are two main motivations to defer this work to the time of hint
application:

1. Some clients, especially terminals using incremental size hints,
   resend XA_WM_NORMAL_HINTS events on resize to avoid fighting with the
   WM or mouse resizing. For example, some terminals like urxvt clear
   PBaseSize and PResizeInc during XResizeWindow and restore them
   afterwards.

   For this reason, after the resize is concluded, we typically receive
   a backlogged XA_WM_NORMAL_HINTS message for each update period with
   movement, which is useless. In some cases one may get hundreds or
   thousands of XA_WM_NORMAL_HINTS messages on large resizes, and
   currently all of these result in a separate updatesizehints() call,
   of which all but the final one are immediately outdated.

   (We can't just blindly discard these messages during resizes like we
   do for EnterNotify, because some of them might actually be for other
   windows, and may not be XA_WM_NORMAL_HINTS events.)

2. For users which use resizehints=0 most of these updates are unused
   anyway -- in the normal case where the client is not floating these
   values won't be used, so there's no need to calculate them up front.

A synthetic test using the mouse to resize a floating terminal window
from roughly 256x256 to 1024x1024 and back again shows that the number
of calls to updatesizehints() goes from over 500 before this patch (one
for each update interval with movement) to 2 after this patch (one for
each hint application), with no change in user visible behaviour.

This also reduces the delay before dwm is ready to process new events
again after a large resize on such a client, as it avoids the thundering
herd of updatesizehints() calls when hundreds of backlogged
XA_WM_NORMAL_HINTS messages appear at once after a resize is finished.
2022-04-16 16:37:46 +02:00
LICENSE Prepare 6.2 release. 2019-02-02 04:50:42 -08:00
Makefile Makefile: just show the compiler output 2018-06-02 17:10:28 +02:00
README update README: remove mentioning the old dextra repo 2018-03-14 21:03:11 +01:00
config.def.h Add a configuration option for fullscreen locking 2021-07-14 11:26:37 +02:00
config.mk bump version to 6.3 2022-01-07 12:39:18 +01:00
drw.c Revert "Improve speed of drw_text when provided with large strings" 2021-08-20 23:09:48 +02:00
drw.h ColBorder has been moved to the enum with ColFg and ColBg. 2018-03-14 17:46:48 +01:00
dwm.1 dwm.1: fix wrong text in man page 2020-07-08 18:05:50 +02:00
dwm.c manage: propertynotify: Reduce cost of unused size hints 2022-04-16 16:37:46 +02:00
dwm.png alternate dwm.png 2006-07-19 14:49:19 +02:00
transient.c applied Peter Hartlichs nice interim Xinerama and map fix patches, for debugging purposes I also added his transient test driver 2011-07-29 20:01:22 +02:00
util.c die() on calloc failure 2016-11-05 11:34:52 +01:00
util.h import new drw from libsl and minor fixes. 2016-06-26 13:52:36 +02:00

README

dwm - dynamic window manager
============================
dwm is an extremely fast, small, and dynamic window manager for X.


Requirements
------------
In order to build dwm you need the Xlib header files.


Installation
------------
Edit config.mk to match your local setup (dwm is installed into
the /usr/local namespace by default).

Afterwards enter the following command to build and install dwm (if
necessary as root):

    make clean install


Running dwm
-----------
Add the following line to your .xinitrc to start dwm using startx:

    exec dwm

In order to connect dwm to a specific display, make sure that
the DISPLAY environment variable is set correctly, e.g.:

    DISPLAY=foo.bar:1 exec dwm

(This will start dwm on display :1 of the host foo.bar.)

In order to display status info in the bar, you can do something
like this in your .xinitrc:

    while xsetroot -name "`date` `uptime | sed 's/.*,//'`"
    do
    	sleep 1
    done &
    exec dwm


Configuration
-------------
The configuration of dwm is done by creating a custom config.h
and (re)compiling the source code.