Description Andrew Flegg (reporter) 2010-07-31 21:53:23 UTC

EXACT STEPS LEADING TO PROBLEM: 
Open http://maemo.org/profile/list/ and page through.

Alternatively, run the following script:

echo -e "Page\tReal\tUser\tSystem"; for i in 1 10 25 50 75 100 150 200 400; do
(time GET -d
http://maemo.org/profile/list/?org_openpsa_qbpager_net_nehmer_account_list_page=$i)
2>&1 | awk '{print $2}' | (read X; read R; read U; read S; echo -e
"$i\t$R\t$U\t$S"); done

EXPECTED OUTCOME:
Each page, whether it be page 1, page 100 or page 400, takes the same time to
render.

Page Real        User       System
1    0m2.643s    0m0.136s   0m0.024s
10   0m2.643s    0m0.136s   0m0.024s
25   0m2.643s    0m0.136s   0m0.024s
50   0m2.643s    0m0.136s   0m0.024s
75   0m2.643s    0m0.136s   0m0.024s
100  0m2.643s    0m0.136s   0m0.024s
150  0m2.643s    0m0.136s   0m0.024s
200  0m2.643s    0m0.136s   0m0.024s
400  0m2.643s    0m0.136s   0m0.024s

ACTUAL OUTCOME:
Each page gets slower to render, suggesting some kind of poorly performing loop
to find the set of entries to return for a given page.

Page Real        User       System
1     0m2.643s   0m0.136s   0m0.024s
10    0m3.790s   0m0.144s   0m0.008s
25    0m5.653s   0m0.140s   0m0.016s
50    0m9.653s   0m0.144s   0m0.012s
75   0m12.370s   0m0.140s   0m0.020s
100  0m17.409s   0m0.140s   0m0.016s
150  0m26.975s   0m0.140s   0m0.016s
200  0m38.599s   0m0.144s   0m0.012s
400  0m43.079s   0m0.132s   0m0.020s

Graph:
http://chart.apis.google.com/chart?chxr=0,0,400|1,0,50&chxs=0,676767,11.5,0,lt,676767|1,676767,11.5,0,lt,676767&chxt=x,y&chs=440x220&cht=lxy&chco=3072F3&chds=0,400,0,50&chd=t:1,10,25,50,75,100,150,200,400|2.6,3.8,5.7,9.7,12.4,17.4,27,38.6,43.1&chdlp=b&chls=2,4,1&chma=5,5,5,25&chtt=Profile+page+render+time


REPRODUCIBILITY:
always

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-GB; rv:1.9.2.7)
Gecko/20100715 Ubuntu/10.04 (lucid) Firefox/3.6.7