Class: MemCache

Inherits:
Object
  • Object
show all
Defined in:
lib/adapters/memcache-client.rb

Overview

Add this line to your ApplicationController (app/controllers/application.rb) to enable logging for memcache-client: custom_benchmark {|runtime| MemCache.cache_runtime(runtime) }

Constant Summary collapse

@@record_size = 
false
@@logger = 
nil
@@error_logger = 
nil
@@cache_latency = 
0.0
@@cache_gets = 
0
@@cache_sets = 
0
@@cache_deletes = 
0
@@cache_hits = 
0
@@cache_misses = 
0
@@get_data_size = 
0
@@set_data_size = 
0

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.cache_runtime(runtime) ⇒ Object 



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# File 'lib/adapters/memcache-client.rb', line 35

def self.cache_runtime(runtime)
  latency,gets,gsize,sets,ssize,deletes,hits,misses = self.get_benchmarks

  # Since we're using memcache store, the reset_benchmarks method call must
  # appear at the beginning of the the request.  This is necessary before
  # Rails saves the session to the store after the entry is written to
  # production.log.  If you don't clear the MemCache stats at the beginning
  # of the request, then the session save from other requests pollutes the
  # cache stats for the subsequent requests.  Use a before_filter in
  # application.rb:
  #   before_filter { MemCache.reset_benchmarks }
  # If you aren't using memcache session store then you uncomment this line:
  # self.reset_benchmarks

  " | memcache: #{sprintf("%.5f,%d,%d,%d,%d,%d,%d,%d",latency,gets,gsize,sets,ssize,deletes,hits,misses)} (#{sprintf("%d", (latency * 100) / runtime)}%)"
end

.get_benchmarks ⇒ Object 



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# File 'lib/adapters/memcache-client.rb', line 31

def self.get_benchmarks
  [@@cache_latency, @@cache_gets, @@get_data_size, @@cache_sets, @@set_data_size, @@cache_deletes, @@cache_hits, @@cache_misses]
end

.reset_benchmarks ⇒ Object 



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# File 'lib/adapters/memcache-client.rb', line 20

def self.reset_benchmarks
  @@cache_latency = 0.0
  @@cache_gets = 0
  @@cache_sets = 0
  @@cache_deletes = 0
  @@cache_hits = 0
  @@cache_misses = 0
  @@get_data_size = 0
  @@set_data_size = 0
end

Instance Method Details

#add_with_benchmark(key, val, expiry = 0, raw = false) ⇒ Object Also known as: add 



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# File 'lib/adapters/memcache-client.rb', line 112

def add_with_benchmark(key, val, expiry=0, raw=false)
  t1 = Time.now
  rescue_no_connection { add_without_benchmark(key, val, expiry, raw) }
  @@cache_latency += Time.now - t1
  @@cache_sets += 1
  size = @@record_size ? (Marshal.dump(val).length rescue 0) : 0
  @@set_data_size += size if @@record_size
  @@logger.info("MEMCACHE ADD #{key} SIZE #{size} TIME #{Time.now - t1}") if @@logger
end

#delete_with_benchmark(key, expiry = 0) ⇒ Object Also known as: delete 



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# File 'lib/adapters/memcache-client.rb', line 124

def delete_with_benchmark(key, expiry=0)
  t1 = Time.now
  rescue_no_connection { delete_without_benchmark(key, expiry) }
  @@cache_latency += Time.now - t1
  @@cache_deletes += 1
  @@logger.info("MEMCACHE DELETE #{key} TIME #{Time.now - t1}") if @@logger
end

#get_multi_with_benchmark(*keys) ⇒ Object Also known as: get_multi 



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# File 'lib/adapters/memcache-client.rb', line 80

def get_multi_with_benchmark(*keys)
  val = nil
  t1 = Time.now
  vals = rescue_no_connection { get_multi_without_benchmark(keys) }
  @@cache_latency += Time.now - t1
  @@cache_gets += 1
  if @@logger or @@record_size
    request_id = t1.to_f.to_s.last(4)
    for key in keys
      size = @@record_size ? (Marshal.dump(vals[key]).length rescue 0) : 0
      @@get_data_size += size if @@record_size
      @@logger.info("MEMCACHE GETMULTI ID #{request_id} KEY #{key} SIZE #{size} TIME #{Time.now - t1}") if @@logger
    end
  end
  vals
end

#get_with_benchmark(key, raw = false) ⇒ Object Also known as: get, [] 



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# File 'lib/adapters/memcache-client.rb', line 64

def get_with_benchmark(key, raw=false)
  val = nil
  t1 = Time.now
  val = rescue_no_connection { get_without_benchmark(key, raw) }
  val.nil? ? (@@cache_misses += 1) : (@@cache_hits += 1)
  @@cache_latency += Time.now - t1
  @@cache_gets += 1
  size = @@record_size ? (Marshal.dump(val).length rescue 0) : 0
  @@get_data_size += size if @@record_size
  @@logger.info("MEMCACHE GET #{key} SIZE #{size} TIME #{Time.now - t1}") if @@logger
  val
end

#rescue_no_connection ⇒ Object 



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# File 'lib/adapters/memcache-client.rb', line 52

def rescue_no_connection
  begin
    yield
  rescue MemCache::MemCacheError => err
    @@error_logger.info([Time.now.to_s, err.message, err.backtrace].compact.join("\n")) if @@error_logger
    if err.message != "No connection to server" and err.message !~ /^lost connection/i and ENV['RAILS_ENV'] != 'development'
      SystemNotifier.deliver_non_controller_exception_notification(err)
    end
    return nil
  end
end

#set_with_benchmark(key, val, expiry = 0, raw = false) ⇒ Object Also known as: set, []= 



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# File 'lib/adapters/memcache-client.rb', line 99

def set_with_benchmark(key, val, expiry=0, raw=false)
  t1 = Time.now
  rescue_no_connection { set_without_benchmark(key, val, expiry, raw) }
  @@cache_latency += Time.now - t1
  @@cache_sets += 1
  size = @@record_size ? (Marshal.dump(val).length rescue 0) : 0
  @@set_data_size += size if @@record_size
  @@logger.info("MEMCACHE SET #{key} SIZE #{size} TIME #{Time.now - t1}") if @@logger
end