diff --git a/utils/lru/README b/utils/lru/README index 288189e3..f043b297 100644 --- a/utils/lru/README +++ b/utils/lru/README @@ -3,11 +3,17 @@ Redis approximated LRU algorithm against the theoretical output of true LRU algorithm. In order to use the program you need to recompile Redis setting the define -REDIS_LRU_CLOCK_RESOLUTION to 1, by editing redis.h. +REDIS_LRU_CLOCK_RESOLUTION to 1, by editing the file server.h. This allows to execute the program in a fast way since the 1 ms resolution is enough for all the objects to have a different enough time stamp during the test. The program is executed like this: - ruby test-lru.rb > /tmp/lru.html + ruby test-lru.rb /tmp/lru.html + +You can optionally specify a number of times to run, so that the program +will output averages of different runs, by adding an additional argument. +For instance in order to run the test 10 times use: + + ruby test-lru.rb /tmp/lru.html 10 diff --git a/utils/lru/test-lru.rb b/utils/lru/test-lru.rb index ee0527ef..dadc6d50 100644 --- a/utils/lru/test-lru.rb +++ b/utils/lru/test-lru.rb @@ -1,112 +1,188 @@ require 'rubygems' require 'redis' -r = Redis.new -r.config("SET","maxmemory","2000000") -r.config("SET","maxmemory-policy","allkeys-lru") -r.config("SET","maxmemory-samples",5) -r.config("RESETSTAT") -r.flushall +$runs = []; # Remember the error rate of each run for average purposes. -puts < - - -
+    .new {
+        border: 1px green solid;
+    }
+
+    .otherdb {
+        border: 1px red solid;
+    }
+
+    .ex {
+        background-color: #666;
+    }
+    
+    
 EOF
 
-# Fill
-oldsize = r.dbsize
-id = 0
-while true
-    id += 1
-    r.set(id,"foo")
-    newsize = r.dbsize
-    break if newsize == oldsize
-    oldsize = newsize
-end
-
-inserted = r.dbsize
-first_set_max_id = id
-puts "#{r.dbsize} keys inserted"
-
-# Access keys sequentially
-
-puts "Access keys sequentially"
-(1..first_set_max_id).each{|id|
-    r.get(id)
-#    sleep 0.001
-}
-
-# Insert more 50% keys. We expect that the new keys
-half = inserted/2
-puts "Insert enough keys to evict half the keys we inserted"
-add = 0
-while true
-    add += 1
-    id += 1
-    r.set(id,"foo")
-    break if r.info['evicted_keys'].to_i >= half
-end
-
-puts "#{add} additional keys added."
-puts "#{r.dbsize} keys in DB"
-
-# Check if evicted keys respect LRU
-# We consider errors from 1 to N progressively more serious as they violate
-# more the access pattern.
-
-errors = 0
-e = 1
-edecr = 1.0/(first_set_max_id/2)
-(1..(first_set_max_id/2)).each{|id|
-    e -= edecr if e > 0
-    e = 0 if e < 0
-    if r.exists(id)
-        errors += e
-    end
-}
-
-puts "#{errors} errors!"
-puts "
"
-
-# Generate the graphical representation
-(1..id).each{|id|
-    # Mark first set and added items in a different way.
-    c = "box"
-    if id <= first_set_max_id
-        c << " old"
-    else
-        c << " new"
+    # Fill the DB up to the first eviction.
+    oldsize = r.dbsize
+    id = 0
+    while true
+        id += 1
+        r.set(id,"foo")
+        newsize = r.dbsize
+        break if newsize == oldsize # A key was evicted? Stop.
+        oldsize = newsize
     end
 
-    # Add class if exists
-    c << " ex" if r.exists(id)
-    puts "
"
-}
+    inserted = r.dbsize
+    first_set_max_id = id
+    html << "#{r.dbsize} keys inserted"
 
-# Close HTML page
+    # Access keys sequentially, so that in theory the first part will be expired
+    # and the latter part will not, according to perfect LRU.
 
-puts <
-
+    STDERR.puts "Access keys sequentially"
+    (1..first_set_max_id).each{|id|
+        r.get(id)
+        sleep 0.001
+        STDERR.print(".") if (id % 150) == 0
+    }
+    STDERR.puts
+
+    # Insert more 50% keys. We expect that the new keys will rarely be expired
+    # since their last access time is recent compared to the others.
+    #
+    # Note that we insert the first 100 keys of the new set into DB1 instead
+    # of DB0, so that we can try how cross-DB eviction works.
+    half = inserted/2
+    html << "Insert enough keys to evict half the keys we inserted"
+    add = 0
+
+    otherdb_start_idx = id+1
+    otherdb_end_idx = id+100
+    while true
+        add += 1
+        id += 1
+        if id >= otherdb_start_idx && id <= otherdb_end_idx
+            r.select(1)
+            r.set(id,"foo")
+            r.select(0)
+        else
+            r.set(id,"foo")
+        end
+        break if r.info['evicted_keys'].to_i >= half
+    end
+
+    html << "#{add} additional keys added."
+    html << "#{r.dbsize} keys in DB"
+
+    # Check if evicted keys respect LRU
+    # We consider errors from 1 to N progressively more serious as they violate
+    # more the access pattern.
+
+    errors = 0
+    e = 1
+    error_per_key = 100000.0/first_set_max_id
+    half_set_size = first_set_max_id/2
+    maxerr = 0
+    (1..(first_set_max_id/2)).each{|id|
+        if id >= otherdb_start_idx && id <= otherdb_end_idx
+            r.select(1)
+            exists = r.exists(id)
+            r.select(0)
+        else
+            exists = r.exists(id)
+        end
+        if id < first_set_max_id/2
+            thiserr = error_per_key * ((half_set_size-id).to_f/half_set_size)
+            maxerr += thiserr
+            errors += thiserr if exists
+        elsif id >= first_set_max_id/2
+            thiserr = error_per_key * ((id-half_set_size).to_f/half_set_size)
+            maxerr += thiserr
+            errors += thiserr if !exists
+        end
+    }
+    errors = errors*100/maxerr
+
+    STDERR.puts "Test finished with #{errors}% error! Generating HTML on stdout."
+
+    html << "#{errors}% error!"
+    html << "
" + $runs << errors + + # Generate the graphical representation + (1..id).each{|id| + # Mark first set and added items in a different way. + c = "box" + if id >= otherdb_start_idx && id <= otherdb_end_idx + c << " otherdb" + elsif id <= first_set_max_id + c << " old" + else + c << " new" + end + + # Add class if exists + if id >= otherdb_start_idx && id <= otherdb_end_idx + r.select(1) + exists = r.exists(id) + r.select(0) + else + exists = r.exists(id) + end + + c << " ex" if exists + html << "
" + } + + # Close HTML page + + html << < + EOF + + f = File.open(filename,"w") + f.write(html) + f.close +end + +def print_avg + avg = ($runs.reduce {|a,b| a+b}) / $runs.length + puts "#{$runs.length} runs, AVG is #{avg}" +end + +if ARGV.length < 1 + STDERR.puts "Usage: ruby test-lru.rb [num-runs]" + exit 1 +end + +filename = ARGV[0] +numruns = 1 + +numruns = ARGV[1].to_i if ARGV.length == 2 + +numruns.times { + testit(filename) + print_avg if numruns != 1 +}