junegunn commented on code in PR #6558:
URL: https://github.com/apache/hbase/pull/6558#discussion_r1899164042
##########
hbase-diagnostics/src/main/java/org/apache/hadoop/hbase/PerformanceEvaluation.java:
##########
@@ -1205,7 +1205,7 @@ private static long nextRandomSeed() {
this.opts = options;
this.status = status;
this.testName = this.getClass().getSimpleName();
- everyN = (long) (opts.totalRows / (opts.totalRows * opts.sampleRate));
+ everyN = (long) (1 / opts.sampleRate);
Review Comment:
AFAIK, we don't have to worry about it because 1.0 (1 / 2<sup>0</sup>) has a
finite binary representation (unlike numbers like 0.1 or 0.2), so `(1 / 1.0)`
will not yield any arithmetic error.
```
irb(main):001> [0].pack('G').bytes.map { "%08b" % it }.join
=> "0000000000000000000000000000000000000000000000000000000000000000"
irb(main):002> [1].pack('G').bytes.map { "%08b" % it }.join
=> "0011111111110000000000000000000000000000000000000000000000000000"
irb(main):003> [0.1].pack('G').bytes.map { "%08b" % it }.join
=> "0011111110111001100110011001100110011001100110011001100110011010"
irb(main):004> [0.2].pack('G').bytes.map { "%08b" % it }.join
=> "0011111111001001100110011001100110011001100110011001100110011010"
```
https://en.wikipedia.org/wiki/Double-precision_floating-point_format#Double-precision_examples
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