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Version 1.9 Build 1367

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Memory Breakdown

The following table is a breakdown of the memory use of the different managers. The column outputs are the amounts of used swap space (in kilobytes) for different amounts of activity. '2 xterms' designates the memory usage for having two available xterms (in the case of olwm and fvwm2 this also includes a console terminal for network and status messages) while the subsequent rows indicate the addition of more xterminals, a netscape session, and an AIPS++ session.

	CDE	fvwm2	twm	olwm
2 xterms	28352	24680	24464	23512
+2 xterms	30176	25832	-	-
+netscape	34480	30032	-	-
+aips++	50560	46384	-	-

I only compared CDE and fvwm2 in all of the categories since they were the only two which supported desktops, considered an essential feature. Overall, twm and olwm do not represent great memory savings for significantly less performance.

In addition, the 'top' utility was also used to assess the memory usage. CDE requires a large amount of resident memory to pay for its sophistication while FVWM2 offers a similar package with a leaner presence.

  PID USERNAME PRI NICE  SIZE   RES STATE   TIME   WCPU    CPU COMMAND

 8880 jmcmulli  33    0 2112K 1704K sleep   0:00  0.03%  0.04% fvwm2
8880 jmcmulli  34    0 2672K 2152K sleep   0:01  0.05%  0.05% twm
9660 jmcmulli  34    0 2208K 1920K sleep   0:00  0.49%  0.38% olwm
9817 jmcmulli  34    0 6376K 5528K sleep   0:01  1.01%  0.24% dtwm

Beyond memory, the color allocation within CDE has also caused problems when interacting with programs within AIPS++ (e.g. aipsview). This is true even without other color intensive processes (e.g. netscape) present.

Overall, the memory use and color consumption of CDE, combined with the disparity between the canonical AIPS++ machine and the typical low-memory IPC's generally in use at Green Bank strongly suggests that the CDE is actually the worst window manager system for those requiring high performance in their AIPS++ applications.