From cfe5234e975b914e831907db77fee8f154950fc1 Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Sun, 3 May 2009 16:16:48 -0700 Subject: Safer timeout handling and test case Timeouts of less than 2 seconds are unsafe due to the lack of subsecond resolution in most POSIX filesystems. This is the trade-off for using a low-complexity solution for timeouts. Since this type of timeout is a last resort; 2 seconds is not entirely unreasonable IMNSHO. Additionally, timing out too aggressively can put us in a fork loop and slow down the system. Of course, the default is 60 seconds and most people do not bother to change it. --- TODO | 2 -- lib/unicorn.rb | 3 +-- lib/unicorn/configurator.rb | 8 +++++--- 3 files changed, 6 insertions(+), 7 deletions(-) diff --git a/TODO b/TODO index 204bb7d..085ef70 100644 --- a/TODO +++ b/TODO @@ -2,8 +2,6 @@ * integration tests with nginx including bad client handling - * tests for timeout - * manpages (why do so few Ruby executables come with proper manpages?) == 1.1.0 diff --git a/lib/unicorn.rb b/lib/unicorn.rb index 54e2bc0..07925f2 100644 --- a/lib/unicorn.rb +++ b/lib/unicorn.rb @@ -375,9 +375,8 @@ module Unicorn # is stale for >@timeout seconds, then we'll kill the corresponding # worker. def murder_lazy_workers - now = Time.now WORKERS.each_pair do |pid, worker| - (now - worker.tempfile.ctime) <= @timeout and next + Time.now - worker.tempfile.ctime <= @timeout and next logger.error "worker=#{worker.nr} PID:#{pid} is too old, killing" kill_worker(:KILL, pid) # take no prisoners for @timeout violations worker.tempfile.close rescue nil diff --git a/lib/unicorn/configurator.rb b/lib/unicorn/configurator.rb index 6f49905..7724ff0 100644 --- a/lib/unicorn/configurator.rb +++ b/lib/unicorn/configurator.rb @@ -143,12 +143,14 @@ module Unicorn # handling the request/app.call/response cycle taking longer than # this time period will be forcibly killed (via SIGKILL). This # timeout is enforced by the master process itself and not subject - # to the scheduling limitations by the worker process. + # to the scheduling limitations by the worker process. Due the + # low-complexity, low-overhead implementation, timeouts of less + # than 2.0 seconds can be considered inaccurate and unsafe. def timeout(seconds) Numeric === seconds or raise ArgumentError, "not numeric: timeout=#{seconds.inspect}" - seconds > 0 or raise ArgumentError, - "not positive: timeout=#{seconds.inspect}" + seconds >= 2 or raise ArgumentError, + "too low: timeout=#{seconds.inspect}" @set[:timeout] = seconds end -- cgit v1.2.3-24-ge0c7