[Lxml-checkins] r42667 - lxml/trunk/doc

[scoder at codespeak.net]

Author: scoder
Date: Fri May  4 11:37:28 2007
New Revision: 42667

Modified:
   lxml/trunk/doc/performance.txt
Log:
tree timings and note on non-comparable absolute numbers

Modified: lxml/trunk/doc/performance.txt
==============================================================================
--- lxml/trunk/doc/performance.txt	(original)
+++ lxml/trunk/doc/performance.txt	Fri May  4 11:37:28 2007
@@ -40,6 +40,13 @@
 running for tree T1, with plain string text (S) and attributes (A).  It was
 run against the root element (R) in the tree structure of the data (T).
 
+Note that very small operations are repeated in integer loops to make them
+measurable.  It is therefore not always possible to compare the absolute
+timings of, say, a single access benchmark (which usually loops) and a 'get
+all in one step' benchmark, which already takes enough time to be measurable
+and is therefore measured as is.  Take a look at the concrete benchmarks in
+the scripts to understand how the numbers compare.
+
 .. contents::
 .. 
    1  Bad things first
@@ -137,20 +144,20 @@
 (given in seconds)::
 
   lxe:       --     S-     U-     -A     SA     UA
-       T1: 0.1029 0.1005 0.0998 0.1003 0.0998 0.1002
-       T2: 0.1035 0.1013 0.1015 0.1090 0.1089 0.1090
-       T3: 0.0276 0.0270 0.0273 0.0679 0.0673 0.0673
-       T4: 0.0004 0.0004 0.0004 0.0013 0.0013 0.0013
+       T1: 0.1155 0.1154 0.1153 0.1159 0.1181 0.1158
+       T2: 0.1183 0.1197 0.1200 0.1267 0.1261 0.1264
+       T3: 0.0341 0.0312 0.0314 0.0726 0.0717 0.0720
+       T4: 0.0005 0.0004 0.0004 0.0014 0.0014 0.0014
   cET:       --     S-     U-     -A     SA     UA
-       T1: 0.0277 0.0273 0.0273 0.0272 0.0278 0.0275
-       T2: 0.0281 0.0347 0.0281 0.0285 0.0284 0.0284
-       T3: 0.0074 0.0074 0.0074 0.0122 0.0102 0.0101
+       T1: 0.0290 0.0271 0.0275 0.0297 0.0273 0.0274
+       T2: 0.0280 0.0280 0.0281 0.0285 0.0283 0.0286
+       T3: 0.0071 0.0072 0.0071 0.0113 0.0096 0.0096
        T4: 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001
   ET :       --     S-     U-     -A     SA     UA
-       T1: 0.1349 0.1962 0.2356 0.1288 0.2642 0.1351
-       T2: 0.3104 0.1344 0.3566 0.3857 0.1354 0.4677
-       T3: 0.0313 0.0325 0.0312 0.0356 0.3803 0.0364
-       T4: 0.0005 0.0005 0.0008 0.0006 0.0007 0.0006
+       T1: 0.1362 0.1985 0.2300 0.1344 0.2672 0.1335
+       T2: 0.3107 0.1386 0.3581 0.3886 0.1388 0.4277
+       T3: 0.0334 0.0332 0.0320 0.0367 0.3769 0.0375
+       T4: 0.0006 0.0005 0.0008 0.0007 0.0007 0.0006
 
 While lxml is still faster than ET in most cases (30-60%), cET can be up to
 three times faster than lxml here.  One of the reasons is that lxml must