[llvm-commits] [PATCH] YAML parser.

[Manuel Klimek]

One first quick note: the yaml parser seems to use about twice as much
memory during parsing (at least on my machine the yaml parser gets my
machine to go into swap stop, while the json parser runs through fine
when using 1GB test data).

With -memory-limit 100 the json parser uses about 500MB VmPeak while
the yaml parser has about 1GB VmPeak.

Cheers,
/Manuel

On Mon, Jan 30, 2012 at 9:08 PM, Michael Spencer <bigcheesegs at gmail.com> wrote:
> Attached is the patch for the YAML parser I've been working on. YAML
> is a super set of JSON that adds many features that I want for writing
> tests for lld (the llvm linker) and other places where we use object
> files.
>
> The API is very similar to the existing JSON API, but is not exactly
> the same as YAML has an extended data model.
>
> This parser is slower than the currently existing JSON parser. For
> files with large scalars, there is almost no difference. For medium
> scalars, there's a ~2x slowdown. And for small scalars, there's a ~6x
> slowdown.
>
> Here are some performance numbers for {yaml,json}-bench -memory-limit
> 100 (a 32bit build can't do much more than that :P). Note that for
> YAML. The Parsing time includes the Tokenizing time.
>
> c:\Users\mspencer\Projects\llvm-project\llvm>yaml-bench -memory-limit 100
> ===-------------------------------------------------------------------------===
>                             YAML parser benchmark
> ===-------------------------------------------------------------------------===
>  Total Execution Time: 5.2104 seconds (5.2185 wall clock)
>
>   ---User Time---   --System Time--   --User+System--   ---Wall
> Time---  --- Name ---
>   2.8392 ( 56.3%)   0.1716 (100.0%)   3.0108 ( 57.8%)   3.0118 (
> 57.7%)  Small Values: Parsing
>   2.1216 ( 42.1%)   0.0000 (  0.0%)   2.1216 ( 40.7%)   2.1257 (
> 40.7%)  Small Values: Tokenizing
>   0.0780 (  1.5%)   0.0000 (  0.0%)   0.0780 (  1.5%)   0.0810 (
> 1.6%)  Small Values: Loop
>   5.0388 (100.0%)   0.1716 (100.0%)   5.2104 (100.0%)   5.2185 (100.0%)  Total
>
> ===-------------------------------------------------------------------------===
>                             YAML parser benchmark
> ===-------------------------------------------------------------------------===
>  Total Execution Time: 0.4836 seconds (0.4740 wall clock)
>
>   ---User Time---   --User+System--   ---Wall Time---  --- Name ---
>   0.2184 ( 45.2%)   0.2184 ( 45.2%)   0.2200 ( 46.4%)  Medium Values: Parsing
>   0.1716 ( 35.5%)   0.1716 ( 35.5%)   0.1710 ( 36.1%)  Medium Values:
> Tokenizing
>   0.0936 ( 19.4%)   0.0936 ( 19.4%)   0.0830 ( 17.5%)  Medium Values: Loop
>   0.4836 (100.0%)   0.4836 (100.0%)   0.4740 (100.0%)  Total
>
> ===-------------------------------------------------------------------------===
>                             YAML parser benchmark
> ===-------------------------------------------------------------------------===
>  Total Execution Time: 0.2496 seconds (0.2480 wall clock)
>
>   ---User Time---   --User+System--   ---Wall Time---  --- Name ---
>   0.0780 ( 31.3%)   0.0780 ( 31.3%)   0.0830 ( 33.5%)  Large Values: Parsing
>   0.0936 ( 37.5%)   0.0936 ( 37.5%)   0.0830 ( 33.5%)  Large Values: Tokenizing
>   0.0780 ( 31.3%)   0.0780 ( 31.3%)   0.0820 ( 33.1%)  Large Values: Loop
>   0.2496 (100.0%)   0.2496 (100.0%)   0.2480 (100.0%)  Total
>
> c:\Users\mspencer\Projects\llvm-project\llvm>json-bench -memory-limit 100
> ===-------------------------------------------------------------------------===
>                             JSON parser benchmark
> ===-------------------------------------------------------------------------===
>  Total Execution Time: 0.6552 seconds (0.6531 wall clock)
>
>   ---User Time---   --System Time--   --User+System--   ---Wall
> Time---  --- Name ---
>   0.5460 ( 87.5%)   0.0312 (100.0%)   0.5772 ( 88.1%)   0.5721 (
> 87.6%)  Small Values: Parsing
>   0.0780 ( 12.5%)   0.0000 (  0.0%)   0.0780 ( 11.9%)   0.0810 (
> 12.4%)  Small Values: Loop
>   0.6240 (100.0%)   0.0312 (100.0%)   0.6552 (100.0%)   0.6531 (100.0%)  Total
>
> ===-------------------------------------------------------------------------===
>                             JSON parser benchmark
> ===-------------------------------------------------------------------------===
>  Total Execution Time: 0.1872 seconds (0.1830 wall clock)
>
>   ---User Time---   --User+System--   ---Wall Time---  --- Name ---
>   0.1092 ( 58.3%)   0.1092 ( 58.3%)   0.1030 ( 56.3%)  Medium Values: Parsing
>   0.0780 ( 41.7%)   0.0780 ( 41.7%)   0.0800 ( 43.7%)  Medium Values: Loop
>   0.1872 (100.0%)   0.1872 (100.0%)   0.1830 (100.0%)  Total
>
> ===-------------------------------------------------------------------------===
>                             JSON parser benchmark
> ===-------------------------------------------------------------------------===
>  Total Execution Time: 0.1716 seconds (0.1620 wall clock)
>
>   ---User Time---   --User+System--   ---Wall Time---  --- Name ---
>   0.0780 ( 45.5%)   0.0780 ( 45.5%)   0.0810 ( 50.0%)  Large Values: Parsing
>   0.0936 ( 54.5%)   0.0936 ( 54.5%)   0.0810 ( 50.0%)  Large Values: Loop
>   0.1716 (100.0%)   0.1716 (100.0%)   0.1620 (100.0%)  Total
>
>
> - Michael Spencer