Add an option to strip leading zeros from linear histograms

Sometimes histogram gives us too much zero info that we don't really care. For example: usec : count distribution 0 : 0 | | 1 : 0 | | 2 : 0 | | 3 : 0 | | 4 : 0 | | 5 : 0 | | 6 : 0 | | 7 : 0 | | 8 : 0 | | 9 : 0 | | 10 : 0 | | 11 : 0 | | 12 : 0 | | 13 : 0 | | 14 : 0 | | 15 : 0 | | 16 : 0 | | 17 : 0 | | 18 : 0 | | 19 : 0 | | 20 : 0 | | 21 : 0 | | 22 : 0 | | 23 : 0 | | 24 : 0 | | 25 : 0 | | 26 : 0 | | 27 : 0 | | 28 : 0 | | 29 : 0 | | 30 : 0 | | 31 : 0 | | 32 : 0 | | 33 : 0 | | 34 : 0 | | 35 : 0 | | 36 : 0 | | 37 : 0 | | 38 : 0 | | 39 : 0 | | 40 : 0 | | 41 : 7 |****************************************| 42 : 2 |*********** | Such much info is hard to analyze by FIRST glance, especially console view After supporting strip leading zeros print_linear_hist("usec", "name", name_print, strip_leading_zero=True) usec : count distribution 41 : 7 |****************************************| 42 : 2 |************* | This is what we really care, and it's clear. Signed-off-by: Edward Wu <[email protected]>
weibang6liu · Jun 4, 2021 · 6699757 · 6699757
1 parent 09404eb
commit 6699757
Showing 1 changed file with 17 additions and 7 deletions.
diff --git a/src/python/bcc/table.py b/src/python/bcc/table.py
@@ -168,7 +168,7 @@ def _print_log2_hist(vals, val_type, strip_leading_zero):
  print(body % (low, high, val, stars,
  _stars(val, val_max, stars)))
 
-def _print_linear_hist(vals, val_type):
+def _print_linear_hist(vals, val_type, strip_leading_zero):
  global stars_max
  log2_dist_max = 64
  idx_max = -1
@@ -186,8 +186,15 @@ def _print_linear_hist(vals, val_type):
  print(header % val_type);
  for i in range(0, idx_max + 1):
  val = vals[i]
- print(body % (i, val, stars,
- _stars(val, val_max, stars)))
+
+ if strip_leading_zero:
+ if val:
+ print(body % (i, val, stars,
+ _stars(val, val_max, stars)))
+ strip_leading_zero = False
+ else:
+ print(body % (i, val, stars,
+ _stars(val, val_max, stars)))
 
 
 def get_table_type_name(ttype):
@@ -650,10 +657,11 @@ def print_log2_hist(self, val_type="value", section_header="Bucket ptr",
  _print_log2_hist(vals, val_type, strip_leading_zero)
 
  def print_linear_hist(self, val_type="value", section_header="Bucket ptr",
- section_print_fn=None, bucket_fn=None, bucket_sort_fn=None):
+ section_print_fn=None, bucket_fn=None, strip_leading_zero=None,
+ bucket_sort_fn=None):
  """print_linear_hist(val_type="value", section_header="Bucket ptr",
  section_print_fn=None, bucket_fn=None,
- bucket_sort_fn=None)
+ strip_leading_zero=None, bucket_sort_fn=None)
 
  Prints a table as a linear histogram. This is intended to span integer
  ranges, eg, from 0 to 100. The val_type argument is optional, and is a
@@ -662,6 +670,8 @@ def print_linear_hist(self, val_type="value", section_header="Bucket ptr",
  each. If section_print_fn is not None, it will be passed the bucket
  value to format into a string as it sees fit. If bucket_fn is not None,
  it will be used to produce a bucket value for the histogram keys.
+ If the value of strip_leading_zero is not False, prints a histogram
+ that is omitted leading zeros from the beginning.
  If bucket_sort_fn is not None, it will be used to sort the buckets
  before iterating them, and it is useful when there are multiple fields
  in the secondary key.
@@ -680,7 +690,7 @@ def print_linear_hist(self, val_type="value", section_header="Bucket ptr",
  section_print_fn(bucket)))
  else:
  print("\n%s = %r" % (section_header, bucket))
- _print_linear_hist(vals, val_type)
+ _print_linear_hist(vals, val_type, strip_leading_zero)
  else:
  vals = [0] * linear_index_max
  for k, v in self.items():
@@ -691,7 +701,7 @@ def print_linear_hist(self, val_type="value", section_header="Bucket ptr",
  # function be rewritten to avoid having one.
  raise IndexError(("Index in print_linear_hist() of %d " +
  "exceeds max of %d.") % (k.value, linear_index_max))
- _print_linear_hist(vals, val_type)
+ _print_linear_hist(vals, val_type, strip_leading_zero)
 
 
 class HashTable(TableBase):