Linux / Kernel
Unit Size

The distribution of size of units (measured in lines of code).

Intro
  • Unit size measurements show the distribution of size of units of code (methods, functions...).
  • Units are classified in four categories based on their size (lines of code): 1-20 (small units), 20-50 (medium size units), 51-100 (long units), 101+ (very long units).
  • You should aim at keeping units small (< 20 lines). Long units may become "bloaters", code that have increased to such gargantuan proportions that they are hard to work with.
Learn more...
Unit Size Overall
  • There are 12,243 units with 183,582 lines of code in units (68.9% of code).
    • 89 very long units (13,126 lines of code)
    • 380 long units (24,940 lines of code)
    • 2,001 medium size units (60,376 lines of code)
    • 3,152 small units (45,827 lines of code)
    • 6,621 very small units (39,313 lines of code)
7% | 13% | 32% | 24% | 21%
Legend:
101+
51-100
21-50
11-20
1-10
Unit Size per Extension
101+
51-100
21-50
11-20
1-10
c7% | 13% | 33% | 25% | 20%
h2% | 11% | 24% | 16% | 45%
Unit Size per Logical Component
primary logical decomposition
101+
51-100
21-50
11-20
1-10
bpf20% | 17% | 29% | 18% | 13%
ROOT5% | 13% | 34% | 25% | 20%
trace5% | 13% | 32% | 27% | 21%
debug22% | 19% | 29% | 19% | 9%
locking7% | 5% | 27% | 27% | 31%
sched2% | 12% | 28% | 27% | 27%
power9% | 11% | 38% | 20% | 19%
events4% | 9% | 38% | 27% | 20%
futex8% | 26% | 38% | 17% | 9%
rcu1% | 21% | 33% | 18% | 25%
cgroup1% | 14% | 41% | 24% | 17%
kcsan13% | 9% | 25% | 26% | 25%
time0% | 7% | 32% | 30% | 28%
printk0% | 20% | 39% | 20% | 19%
dma0% | 15% | 29% | 28% | 26%
irq0% | 5% | 33% | 33% | 26%
livepatch0% | 8% | 47% | 22% | 20%
gcov0% | 0% | 41% | 30% | 28%
entry0% | 0% | 46% | 22% | 31%
Alternative Visuals
Longest Units
Top 50 longest units
Unit# linesMcCabe index# params
386 102 1
306 32 2
287 71 2
282 110 6
263 86 1
249 59 3
239 61 4
231 59 3
210 125 3
196 60 5
193 83 8
191 53 5
185 57 4
181 57 5
178 46 1
176 48 4
173 64 5
170 52 3
169 53 4
168 46 2
166 54 3
166 43 3
165 67 4
162 43 3
158 50 1
156 35 1
153 31 3
148 30 2
147 59 3
144 25 3
143 33 4
142 40 2
142 38 1
136 39 5
136 16 2
136 43 2
136 42 3
135 40 7
135 29 5
135 39 2
133 64 1
133 38 4
132 4 1
132 31 5
131 51 2
130 38 3
129 47 1
128 36 3
126 35 2
125 39 1