Track SQL statement execution times, so that they can be profiled.

[quanlib.git] / tconn.rb

diff --git a/tconn.rb b/tconn.rb
new file mode 100644 (file)
index 0000000..43fa0f5
--- /dev/null
+++ b/tconn.rb
@@ -0,0 +1,71 @@
+# tconn.rb
+#
+# Timed Connection:  
+# Wrapper around a PG Connection that provides a report on where time was spent executing SQL
+#
+
+require 'pg'
+
+class TimedConn 
+  def initialize(wrapped_conn)
+    @conn = wrapped_conn
+    @stmts = {}
+    @total_time = 0
+  end
+
+  def close
+    @conn.close()
+    puts "Connection closing.  Total SQL time:  " + @total_time.to_s + " secs"
+    @stmts.each do |sql, info| 
+      elapsed = info[2]
+      calls = info[1]
+      puts elapsed.to_s + " secs: " + calls.to_s + " times:  " + sql
+    end
+  end
+
+  def exec(*args, &block)
+    before = Time.now
+    #puts args.inspect
+    result = @conn.exec(*args)
+    #puts result.inspect
+    after = Time.now
+    elapsed = (after - before)
+    remember(args[0], elapsed)
+    @total_time += elapsed
+    if block_given?
+      yield(result)
+    else
+      return result
+    end
+  end
+
+  def exec_params(*args, &block)
+    before = Time.now
+    #puts args.inspect
+    result = @conn.exec_params(*args)
+    #puts result.inspect
+    after = Time.now
+    elapsed = (after - before)
+    remember(args[0], elapsed)
+    @total_time += elapsed
+    if block_given?
+      yield(result)
+    else
+      return result
+    end
+  end
+
+  def remember(sql, elapsed)
+    if @stmts.has_key?(sql)
+      stmt = @stmts[sql]
+    else
+      stmt = [sql, 0, 0]
+    end
+
+    stmt[1] += 1  # Number of times this statement has been invoked
+    stmt[2] += elapsed   # total elapsed time spent on this statement
+    
+    @stmts[sql] = stmt
+  end
+end
+