The current __compute method of account_account is wasting a lot of time reordering the list of accounts to compute.
We can make the next block of code about five times faster with a small one-line optimization (just adding a "ids2.reverse()" line):
--------
brs = list(self.browse(cr, uid, ids2, context=context))
sums = {}
while brs:
current = brs[0]
can_compute = True
for child in current.child_id:
if child.id not in sums:
can_compute = False
try:
brs.insert(0, brs.pop(brs.index(child)))
except ValueError:
brs.insert(0, child)
if can_compute:
brs.pop(0)
for fn in field_names:
sums.setdefault(current.id, {})[fn] = accounts.get(current.id, {}).get(fn, 0.0)
if current.child_id:
sums[current.id][fn] += sum(sums[child.id][fn] for child in current.child_id)
--------
That code is computing the value of each account as the sums of the account values plus its children values.
The problem is that the list of the accounts is sorted on the worst posible way! So most of time is wasted reordering that list.
The list of accounts comes from _get_children_and_consol, that returns a list of accounts in the form [parent, child1, child2, child1_of_child2, child2_of_child2, child3].
So the block of code shown above, that always tries to compute the first element of the list, but he won't be able to do it without computing the children accounts first: so it ends up poping accounts from the list and puting them back at the begining of the list in the reverse order... that is, it wastes a lot of time just to reverse the list on the most expensive way!
Adding a ids2.reverse() line before the block of code, will mean that the list of accounts will be in the form [child3, child2_of_child2, child1_of_child2, child2, child1, parent] so no poping&inserting will be necesary!
We have timed that block of code before adding the "ids2.reverse()" and after it:
BLOCK FULL METHOD
Original: 2.1701090335825 2.370021998875
Optimized: 0.37584179639849996 0.50867897272100004 (4.65 times faster!)
Note: Average times after several runs, getting the debit and credit of the root account on a database with 1663 accounts and 6930 account move lines.
I think this should be fixed ASAP: It will soothe the currents problems with accounting reports (like the general ledger performance problems reported on bug 514808 and bug 551630).
account_account; 378
account_move_line; 3944
account_move; 1303
account_period; 84
all periods open - with patch mentioned on expert list regarding real time computation of all open fy
response of chart of account < 1 sec