Signed-off-by: Junchang Wang <junchangwang@xxxxxxxxx>
---
count/count.tex | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/count/count.tex b/count/count.tex
index cc47554..6dfc7a6 100644
--- a/count/count.tex
+++ b/count/count.tex
@@ -1258,13 +1258,13 @@ machine.
fast and scalable while allowing readers to also enjoy
reasonable performance and scalability?
\QuickQuizAnswer{
- One approach would be to maintain a global approximation
- to the value.
- Readers would increment their per-thread variable, but when it
- reached some predefined limit, atomically add it to a global
- variable, then zero their per-thread variable.
- This would permit a tradeoff between average increment overhead
- and accuracy of the value read out.
+ One approach would be to add a global variable maintaining a
+ approximation to the exact value. An updater would increment its
+ per-thread variable, and when its value reaches predefined limit,
+ atomically add the value to the global variable, then zero its
+ per-thread variable. Readers simply return the value of global variable,
+ enjoying reasonable performance. This would permit a tradeoff between
+ average increment overhead and accuracy of the value read out.
The reader is encouraged to think up and try out other approaches,
for example, using a combining tree.
--
2.7.4
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