[Kmymoney-devel] Is there a cache for accounts balance?

[Alvaro Soliverez]

On Fri, Sep 10, 2010 at 12:10 AM, Fernando Vilas <fvilas at iname.com> wrote:
> On Sunday, September 05, 2010 10:50:58 Alvaro Soliverez wrote:
>> On Sun, Aug 29, 2010 at 5:09 PM, Fernando Vilas <fvilas at iname.com> wrote:
>> > On Sunday, August 29, 2010 11:10:46 Thomas Baumgart wrote:
>> >> Hi,
>> >>
>> >> on Sunday 29 August 2010 16:24:30 Alvaro Soliverez wrote:
>> >> > Hello all,
>> >> > I've been doing some callgrind tests to check the startup performance.
>> >> > One thing I noticed is that almost a 10% of the time is spent
>> >> > calculating balances.
>> >> > For a normal start, balances are needed by forecast, reports and the
>> >> > home
>> >> >
>> >> >  view.
>> >> >
>> >> > Do you think it would be worth to cache the balance data on
>> >> > MyMoneyFile?
>> >>
>> >> That's already done. Once the XML file is loaded, the method
>> >> MyMoneySeqAccessMgr::rebuildAccountBalances() is called which caches the
>> >> balance with each MyMoneyAccount object.
>> >>
>> >> Also, MyMoneySeqAccessMgr::balance() maintains a cache.
>> >>
>> >> The problem is, that you cannot cache 'the' balance of an account, as it
>> >> may be different for each date.
>> >
>> > There was something similar in the DB backend, but I removed it some time
>> > ago when trying to debug account balance inconsistencies.
>> >
>> > I think we should move the balance cache from the backends into the
>> > MMFile object, so we have a common cache. As Thomas says, it also needs
>> > to handle multiple dates.
>>
>> The cache of course should be per account, per date. As there is not a
>> single balance per account.
>> On a similar note, forecast performance might be improved if I change
>> it from requesting a balance in the past and calculating the balance
>> forward, to requesting the current balance, and calculate the past
>> balances backward. At least for the historic method, I think that
>> might result in a performance improvement.
>
> Is there any opposition to moving this to the MyMoneyFile layer? If not, I
> will sign up to implement it before the January feature freeze.
>

+1