ERROR: Margin is too small (BUG?)

From: Mauricio Carrillo Tripp (trippm_at_gmail.com)
Date: Wed Aug 03 2005 - 10:02:42 CDT

Hi,
I'm trying to minimize-heat-equilibrate a membrane. The minimization goes
well, and if I run after
that with the langevinPiston turned off it seems to run fine too, but when I
turn langevinPiston on
something happens and I get an error saying that the margin is to small. I
tried increasing its
value and this seems to solve the problem to some extent, but then the
simulation gets REALLY
slow. The output below was with margin 5. I have used this same
procedure/config (with other systems)
before succesfully. Is this really a bug as the output says?
________________________________________________________________________________
ETITLE: TS BOND ANGLE DIHED IMPRP ELECT VDW BOUNDARY MISC KINETIC TOTAL TEMP
TOTAL2 TOTAL3 TEMPAVG PRESSURE GPRESSURE VOLUME PRESSAVG GPRESSAVG

ENERGY: 0 39.3568 554.9375 11762.9435 0.0000 -759979.6963 -763.7764 0.0000
0.0000 0.0000 -748386.2349 0.0000 -748386.2349 -748386.2349 0.0000 -
57210.1063 -57210.1063 254062.7345 -57210.1063 -57210.1063

TCL: Setting parameter langevinPiston to off
TCL: Running for 10 steps
ETITLE: TS BOND ANGLE DIHED IMPRP ELECT VDW BOUNDARY MISC KINETIC TOTAL TEMP
TOTAL2 TOTAL3 TEMPAVG PRESSURE GPRESSURE VOLUME PRESSAVG GPRESSAVG

ENERGY: 0 39.3568 554.9375 11762.9435 0.0000 -759979.6963 -763.7764 0.0000
0.0000 0.0000 -748386.2349 0.0000 -747670.2858 -750355.0949 0.0000 -
56818.4041 -56818.4041 254062.7345 -56818.4041 -56818.4041

OPENING EXTENDED SYSTEM TRAJECTORY FILE
TCL: Writing to files with basename step02-heat.
WRITING EXTENDED SYSTEM TO OUTPUT FILE AT STEP 10
WRITING COORDINATES TO OUTPUT FILE AT STEP 10
WRITING VELOCITIES TO OUTPUT FILE AT STEP 10
TCL: Setting parameter langevinPiston to on
TCL: Running for 10 steps
ERROR: Stray PME grid charges detected: 11 sending to 5 for planes 23
ERROR: Stray PME grid charges detected: 9 sending to 5 for planes 23
ERROR: Stray PME grid charges detected: 1 sending to 10 for planes 43
ERROR: Stray PME grid charges detected: 8 sending to 5 for planes 23
ERROR: Stray PME grid charges detected: 13 sending to 4 for planes 16 17
ERROR: Stray PME grid charges detected: 15 sending to 4 for planes 16
ERROR: Margin is too small for 22 atoms during timestep 15.
ERROR: Incorrect nonbonded forces and energies may be calculated!
BUG ALERT: Stray PME grid charges detected!

BUG ALERT: NAMD has detected a bug. Please notify namd_at_ks.uiuc.edu.
------------- Processor 0 Exiting: Called CmiAbort ------------
Reason: BUG ALERT: Stray PME grid charges detected!

BUG ALERT: NAMD has detected a bug. Please notify namd_at_ks.uiuc.edu.
________________________________________________________________________________

-- 
Mauricio Carrillo Tripp, PhD
Department of Chemistry
Wabash College
trippm_at_wabash.edu
http://trippm.bajacast.com/

This archive was generated by hypermail 2.1.6 : Wed Feb 29 2012 - 05:18:56 CST