Re: [PATCH 4/9] refs/reftable: don't recompute committer ident

> Patrick Steinhardt <ps@pks.im> writes:
> 
> > In order to write reflog entries we need to compute the committer's
> > identity as it becomes encoded in the log record itself. In the reftable
> > backend, computing the identity is repeated for every single reflog
> > entry which we are about to write in a transaction. Needless to say,
> > this can be quite a waste of effort when writing many refs with reflog
> > entries in a single transaction.
> 
> It would have been nice to mention which caller benefits from this
> rewrite in the above.
> 
> There are four callers of the fill_reftable_log_record() function.
> The patch moves the split_ident() call from the callee to these four
> callers.  The write_transaction_table() function calls it in a loop,
> which should give us a big boost.  For other three callers, they
> call it at most twice (i.e. write_copy_table() when deleting the old
> one), so their contribution to the boost should be minimal.
> 
> Makes sense.