Stability and Memory Pressure in 8.2

[pgf at laptop.org]

c. scott ananian wrote:
 > On Tue, Sep 9, 2008 at 7:02 AM, Tomeu Vizoso <tomeu at tomeuvizoso.net> wrote:
 > > stability issue? AFAIK, we haven't seen OOM conditions without any
 > > activity open.
 > 
 > Yes, we have.  In particular, if you update your system and then leave
 > it for a while, and later click the software update control panel, you
 > end up OOMing in the control panel.  Sugar restarts and reports are
 > that software update "works fine the second time".  So this might well
 > be a sugar leak; killing 'sugar' is not good for stability.


i think there's definitely a sugar shell leak.  here's some
partial data, gathered from a few machines on my desk right now.

(be careful with the column headings -- i rearranged partway through
to get separate CODE and DATA columns.)

(also, don't do an absolute compare between the 708 build and the
759 build -- the latter is chock full of activites, the former
has none at all.)


build 708:
top - 17:45:17 up 59 min,  3 users,  load average: 0.03, 0.05, 0.01
 PID USER      PR  NI  VIRT  RES  SHR CODE DATA %MEM COMMAND
1741 olpc      15   0 53128  27m  13m    4  14m 12.2 python

same build 708, roughly twenty minutes later:
top - 18:03:16 up  1:17,  3 users,  load average: 0.01, 0.01, 0.00
 PID USER      PR  NI  VIRT  RES  SHR CODE DATA %MEM COMMAND
1741 olpc      15   0 53308  28m  13m    4  14m 12.3 python

build 759:
top - 12:20:00 up 39 min,  4 users,  load average: 0.00, 0.06, 0.11
 PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
1461 olpc      20   0 60576  33m  14m S  0.3 14.5   0:48.38 python

same build 759, almost two hours later:
top - 14:04:11 up  2:23,  3 users,  load average: 0.04, 0.06, 0.08
 PID USER      PR  NI  VIRT  RES  SHR CODE DATA %MEM COMMAND
1461 olpc      20   0 65964  38m  14m    4  23m 16.7 python

finally, i have a joyride-2263, which has been up for 6 days.  i
don't have copy/paste access to it, but the sugar shell is currently
taking 99.6m VIRT, 64m RES, 14m SHR, and is using 28% of system memory.

paul

p.s.  in addition, i think a lot of system processes have grown
somewhat.  for instance, "login" now has 100k more DATA space in
759 than it had in 708.  others (e.g., xinit) haven't grown at
all.  (also "measured" with top.)


=---------------------
 paul fox, pgf at laptop.org