Re: [Monotone-devel] speed of "mtn ls branches"

[William Uther]

On 17/01/2008, at 5:46 PM, Tony Tung wrote:

> Well, I run "ls branches" as part of my shell completion, so 0.2  
> seconds does seem like an eternity. :)  In any case, adding "-- 
> ignore-suspend-certs" does not make any difference.

Hrm, it appears you are correct.  The reason seems to be the  
correctness issue I mentioned at the end of my last email:

> Note that there is a subtle bug/design choice here: If the only  
> instance of a revision on a particular branch happens to have an  
> invalid branch cert (i.e. you have no valid branch certs with that  
> branch), then the 'mtn ls branches' code without suspend cert  
> checks (either the old code, or with --ignore-suspend-certs) will  
> return it anyway.  The code with suspend cert checks will not  
> return that as a valid branch, even though it isn't suspended.

It appears that the 'ls branches' code is currently _always_ checking  
that the certs are valid by finding the heads of each branch.  To  
make --ignore-suspend-certs return a quick-and-dirty list rather than  
the validity-checked list, one could make the following change:

# patch "cmd_list.cc"
#  from [bd12d9df9a26a4fc189681a3a374a211357ab9d2]
#    to [d776611e29b3a5f1b99fb0d67c4a0e12895dfa5d]
#
============================================================
--- cmd_list.cc bd12d9df9a26a4fc189681a3a374a211357ab9d2
+++ cmd_list.cc d776611e29b3a5f1b99fb0d67c4a0e12895dfa5d
@@ -281,7 +281,7 @@ CMD(branches, "branches", "", CMD_REF(li

   globish exc(app.opts.exclude_patterns);
   set<branch_name> names;
-  app.get_project().get_branch_list(inc, names);
+  app.get_project().get_branch_list(inc, names, ! 
app.opts.ignore_suspend_certs);

   for (set<branch_name>::const_iterator i = names.begin();
        i != names.end(); ++i)

I'm not sure if that should be committed or not.  It reduces 'time ls  
branches --ignore-suspend-certs' on my monotone db from 7s down to  
less than 0.1s.  But it means ignoring the validity of certs in this  
case.

Thoughts?

Will      :-}