Comment 1 for bug 857335

With emacs trunk @ revno 105885 (117328 revisions with merged revisions),
1136 tags with two of them on revisions not present in the branch ancestry
(i.e. 'bzr tags' display them with ??? 'bzr tags -r1..' filter them out):

time bzr tags -d ~/src/emacs/trunk >/dev/null

real 0m9.668s
user 0m9.500s
sys 0m0.110s

time bzr tags -d ~/src/emacs/trunk -r1.. >/dev/null

real 19m40.957s
user 19m35.990s
sys 0m2.070s

time ./bzr tags -d ~/src/emacs/trunk -r1.. >/dev/null

real 0m10.056s
user 0m9.970s
sys 0m0.060s

With gcc trunk @ revno 100609 (102370 revisions with merged revisions), 2663
tags, only 27 present in the branch history:

time bzr tags -d /caviar3/vila-tests/gcc/trunk >/dev/null

real 0m5.812s
user 0m5.680s
sys 0m0.120s

time bzr tags -r1.. -d /caviar3/vila-tests/gcc/trunk >/dev/null

real 74m37.331s
user 74m22.950s
sys 0m7.670s

time ./bzr tags -r1.. -d /caviar3/vila-tests/gcc/trunk >/dev/null

real 0m5.758s
user 0m5.660s
sys 0m0.080s