Severe slow-down in plotting

[jdemeyer]

Plotting has severely slowed down since sage-4.8.

For example the following command (inspired on a doctest from devel/sage/sage/plot/plot.py):

sage: timeit('''plot(sin(x),(x,0,2*pi),ticks=pi/3,tick_formatter=pi).save("/tmp/1.png")''', number=1, repeat=20)

It's annoying to measure this as the timing has quite a large standard deviation. But on boxen.math, with sage-4.8, the best case timing is about 1 second, while with sage-5.0.beta13, the best case timing is about 1.5 seconds.

[kcrisman]

This is due to the change in attachment:trac-11915-matplotlib-1.1.0-upgrade.patch:ticket:11915 that reads

figure.tight_layout() 

Comment it out and see the times go down. See #11915 for the rationale behind adding this, which I will point out was not arbitrary.

[jdemeyer]

So should we simply keep the tight_layout() and live with it?