launchpad-dev team mailing list archive

[John Arbash Meinel <john@xxxxxxxxxxxxxxxxx>]

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On 1/27/2011 4:46 PM, John Arbash Meinel wrote:
...

> The one link which was *really* slow was: "view changes to this file"
>  http://localhost:8080/devel/changes?filter_file_id=ez_setup.py-20090421205932-napgtlfomiuomid3-3
> 
> Getting information for ChangeLogUI: 85.644 secs
> 
>   On a second run it dropped to:
> Getting information for ChangeLogUI: 36.571 secs
> 
>   But on the pqm-branch it was:
> Getting information for ChangeLogUI: 3.401 secs
> Getting information for ChangeLogUI: 2.964 secs
> 

lp:///~jameinel/loggerhead/fast_merged_into_revs

Consider it poked. Here are the numbers:

pqm	history-db-trunk	optimized-for-history-db
3s	36s			0.187s

So about 16x faster than what is running in codebrowse today, and almost
200x faster than what is in trunk today.

We can still do a bit better, by crafting the right query from the
start, rather than passing over the data a couple of times.

I do want to point out that this is the sort of stuff I implemented
history-db for. I can't say that I'll have caught all possible
performance regressions for loggerhead as it exists today. I *can* say
that the structure of the database is such that if it is slow, it is
probably because you are doing it wrong.

John
=:->
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