std.xml2 (collecting features)

[Jacob Carlborg via Digitalmars-d]

On 2015-05-03 19:39, Robert burner Schadek wrote:

> Not much code yet, I'm currently building the performance test suite
> https://github.com/burner/std.xml2

There are a couple of interesting comments about the Tango pull parser 
that can be worth mentioning:

* Use -version=whitespace to retain whitespace as data nodes. We see a 
%25 increase in token count and 10% throughput drop when parsing 
"hamlet.xml" with this option enabled (pullparser alone)

* The parser is constructed with some tradeoffs relating to document 
integrity. It is generally optimized for well-formed documents, and 
currently may read past a document-end for those that are not well formed

* Making some tiny unrelated change to the code can cause notable 
throughput changes. We're not yet clear why these swings are so 
pronounced (for changes outside the code path) but they seem to be 
related to the alignment of codegen. It could be a cache-line issue, or 
something else

The last comment might not relevant anymore since these are all quite 
old comments.

-- 
/Jacob Carlborg