Use posix-spawn to instead of Kernel#exec to get better performance

Jason Lee
1 parent 2b1ea36b
Showing 4 changed files with 23 additions and 5 deletions Show diff stats
CHANGELOG.md
letter_avatar.gemspec
lib/letter_avatar/avatar.rb
lib/letter_avatar/version.rb
@@ -0,0 +1,5 @@
+0.1.5
+-----
+
+- Use [posix-spawn](https://github.com/rtomayko/posix-spawn) to instead of Kernel#exec to get better performance.
+  > fork(2) calls slow down as the parent process uses more memory due to the need to copy page tables.
@@ -20,6 +20,8 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ["lib"]
  
+  spec.add_dependency 'posix-spawn', '>= 0.3.0'
+
   spec.add_development_dependency "bundler", "~> 1.3"
   spec.add_development_dependency "rake"
 end
@@ -12,6 +12,8 @@ module LetterAvatar
  
     FILL_COLOR = 'rgba(255, 255, 255, 0.65)'.freeze
  
+    FONT_FILENAME = File.join(File.expand_path("../../", File.dirname(__FILE__)), "Roboto-Medium")
+
     class << self
  
       class Identity
@@ -64,21 +66,30 @@ module LetterAvatar
         color = identity.color
         letter = identity.letter
  
+
         filename = fullsize_path(identity)
  
-        instructions = %W{
+        commands = %W(
+          convert
           -size 240x240
           xc:#{to_rgb(color)}
           -pointsize 140
-          -font Roboto-Medium
+          -font #{FONT_FILENAME}
           -weight 500
           -fill '#{FILL_COLOR}'
           -gravity Center
           -annotate -0+10 '#{letter}'
           '#{filename}'
-        }
+        )
  
-        `convert #{instructions.join(" ")}`
+        command = commands.join(' ')
+
+        pid, stdin, stdout, stderr = POSIX::Spawn.popen4(command)
+        Process.waitpid(pid)
+        err = stderr.read
+        if err != nil && err.length > 0
+          raise "letter_avatar error: #{err.strip}"
+        end
  
         filename
       end
 module LetterAvatar
-  VERSION = "0.1.4"
+  VERSION = "0.1.5"
 end
...	...	@@ -0,0 +1,5 @@
	1	+0.1.5
	2	+-----
	3	+
	4	+- Use [posix-spawn](https://github.com/rtomayko/posix-spawn) to instead of Kernel#exec to get better performance.
	5	+ > fork(2) calls slow down as the parent process uses more memory due to the need to copy page tables.
...	...
...	...	@@ -20,6 +20,8 @@ Gem::Specification.new do \|spec\|
20	20	spec.test_files = spec.files.grep(%r{^(test\|spec\|features)/})
21	21	spec.require_paths = ["lib"]
22	22
	23	+ spec.add_dependency 'posix-spawn', '>= 0.3.0'
	24	+
23	25	spec.add_development_dependency "bundler", "~> 1.3"
24	26	spec.add_development_dependency "rake"
25	27	end
...	...
...	...	@@ -12,6 +12,8 @@ module LetterAvatar
12	12
13	13	FILL_COLOR = 'rgba(255, 255, 255, 0.65)'.freeze
14	14
	15	+ FONT_FILENAME = File.join(File.expand_path("../../", File.dirname(__FILE__)), "Roboto-Medium")
	16	+
15	17	class << self
16	18
17	19	class Identity
...	...	@@ -64,21 +66,30 @@ module LetterAvatar
64	66	color = identity.color
65	67	letter = identity.letter
66	68
	69	+
67	70	filename = fullsize_path(identity)
68	71
69		- instructions = %W{
	72	+ commands = %W(
	73	+ convert
70	74	-size 240x240
71	75	xc:#{to_rgb(color)}
72	76	-pointsize 140
73		- -font Roboto-Medium
	77	+ -font #{FONT_FILENAME}
74	78	-weight 500
75	79	-fill '#{FILL_COLOR}'
76	80	-gravity Center
77	81	-annotate -0+10 '#{letter}'
78	82	'#{filename}'
79		- }
	83	+ )
80	84
81		- `convert #{instructions.join(" ")}`
	85	+ command = commands.join(' ')
	86	+
	87	+ pid, stdin, stdout, stderr = POSIX::Spawn.popen4(command)
	88	+ Process.waitpid(pid)
	89	+ err = stderr.read
	90	+ if err != nil && err.length > 0
	91	+ raise "letter_avatar error: #{err.strip}"
	92	+ end
82	93
83	94	filename
84	95	end
...	...
1	1	module LetterAvatar
2		- VERSION = "0.1.4"
	2	+ VERSION = "0.1.5"
3	3	end
...	...