Export CacheMetric as hits+total, rather than hits+misses, as it's easier to derive hit ratio from that

This commit is contained in:
Paul "LeoNerd" Evans 2015-03-09 20:35:33 +00:00
parent 1748605c5d
commit cbc0406be8
2 changed files with 9 additions and 8 deletions

View File

@ -134,7 +134,7 @@ class TimerMetric(CounterMetric):
class CacheMetric(object):
"""A combination of two CounterMetrics, one to count cache hits and one to
count misses, and a callback metric to yield the current size.
count a total, and a callback metric to yield the current size.
This metric generates standard metric name pairs, so that monitoring rules
can easily be applied to measure hit ratio."""
@ -142,8 +142,8 @@ class CacheMetric(object):
def __init__(self, name, size_callback, labels=[]):
self.name = name
self.hits = CounterMetric(name + ":hits", labels=labels)
self.misses = CounterMetric(name + ":misses", labels=labels)
self.hits = CounterMetric(name + ":hits", labels=labels)
self.total = CounterMetric(name + ":total", labels=labels)
self.size = CallbackMetric(name + ":size",
callback=size_callback,
@ -152,9 +152,10 @@ class CacheMetric(object):
def inc_hits(self, *values):
self.hits.inc(*values)
self.total.inc(*values)
def inc_misses(self, *values):
self.misses.inc(*values)
self.total.inc(*values)
def render(self):
return self.hits.render() + self.misses.render() + self.size.render()
return self.hits.render() + self.total.render() + self.size.render()

View File

@ -140,7 +140,7 @@ class CacheMetricTestCase(unittest.TestCase):
self.assertEquals(metric.render(), [
'cache:hits 0',
'cache:misses 0',
'cache:total 0',
'cache:size 0',
])
@ -149,7 +149,7 @@ class CacheMetricTestCase(unittest.TestCase):
self.assertEquals(metric.render(), [
'cache:hits 0',
'cache:misses 1',
'cache:total 1',
'cache:size 1',
])
@ -157,6 +157,6 @@ class CacheMetricTestCase(unittest.TestCase):
self.assertEquals(metric.render(), [
'cache:hits 1',
'cache:misses 1',
'cache:total 2',
'cache:size 1',
])