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1、While writing Inklog, Ive been debating with myself regarding my use of the filesystem as a datastore. While the filesystem certainly makes creating, updating, visualizing, backing up, and restoring data much easier than it would be in a database, it adds many hardships. First of all, the convenienc
2、e of SQL is thrown out the window. While it is nice that using the filesystem doesnt require a database server, not being able to use a database server means that more programming is involved. Additionally, things like searching through all the entries in the system become difficult, not to mention
3、slow. Another downfall is that the filesystem limits the amount of metadata for each entry that can be kept in a simple fashion.However, the biggest question on my mind was whether or not using a database server would be faster or slower when performing the most commonly requested actions: getting a
4、 list of recent items from the entire system, getting a list of items from a category, and getting one item. I decided to write a test case.I created 6000 empty files in 20 directories. I also created a table in a mysql database that simulated the filesystem: name, mtime, dir, data. I added indexes
5、on dir, name, and mtime. Then I started testing. In each case the test is run 10 times. Then the average is displayed. For the database tests, mysql_connect is called each time.Getting the filenames of the 10 most recent entries from the entire system.FILESYSTEMTIME: 1.7814919948578TIME: 1.742520093
6、9178TIME: 1.8071219921112TIME: 1.6778069734573TIME: 1.6711789369583TIME: 1.7414019107819TIME: 1.6959699392319TIME: 1.6531630754471TIME: 1.7546479701996TIME: 1.6758890151978TOT TIME: 17.201191902161AVG TIME: 1.5637447183782DATABASETIME: 0.0039100646972656TIME: 0.001039981842041TIME: 0.000950932502746
7、58TIME: 0.00096702575683594TIME: 0.00095295906066895TIME: 0.00098395347595215TIME: 0.0009620189666748TIME: 0.0009760856628418TIME: 0.00094294548034668TIME: 0.00095808506011963TOT TIME: 0.012644052505493AVG TIME: 0.0011494593186812Getting the filenames of the 10 most recent files in a single director
8、y.FILESYSTEMTIME: 0.055459976196289TIME: 0.053847074508667TIME: 0.044721961021423TIME: 0.043873071670532TIME: 0.043742060661316TIME: 0.043787956237793TIME: 0.043717980384827TIME: 0.04374098777771TIME: 0.043833017349243TIME: 0.04370105266571TOT TIME: 0.46042513847351AVG TIME: 0.041856830770319DATABAS
9、ETIME: 0.0095839500427246TIME: 0.0055500268936157TIME: 0.005547046661377TIME: 0.0055389404296875TIME: 0.0056079626083374TIME: 0.00553297996521TIME: 0.005499005317688TIME: 0.0055099725723267TIME: 0.0053470134735107TIME: 0.0053049325942993TOT TIME: 0.059021830558777AVG TIME: 0.0053656209598888Getting
10、one item.FILESYSTEMTIME: 0.00032293796539307TIME: 0.00021898746490479TIME: 0.00017297267913818TIME: 0.00016999244689941TIME: 0.00027298927307129TIME: 0.00017201900482178TIME: 0.00016689300537109TIME: 0.00016403198242188TIME: 0.0001760721206665TIME: 0.00017201900482178TOT TIME: 0.0020089149475098AVG
11、TIME: 0.0001826286315918DATABASETIME: 0.0042519569396973TIME: 0.0011199712753296TIME: 0.0010420083999634TIME: 0.0010360479354858TIME: 0.0010439157485962TIME: 0.0010349750518799TIME: 0.001041054725647TIME: 0.0010310411453247TIME: 0.0010330677032471TIME: 0.0064520835876465TOT TIME: 0.019086122512817AV
12、G TIME: 0.0017351020466198The database was 1360 times faster than the filesystem when looking for the 10 most recent items in the entire system. The database was 7.8 times faster when looking for the 10 most recent items in a single directory. However, the filesystem was 9.5 times faster at getting
13、a single file.These numbers skew greater and greater towards the database as the number of items increases. And, in the one place that the filesystem wins, the operation being performed is so un-time-consuming in general, that the increase in the speed of the filesystem doesnt amount to much.These t
14、ests were performed with the database being on the same server as the running script. Additionally, the server performing these actions was, basically, not performing anything else at the time. If your database server is only accessible over a 2400bps modem link, your results will differ greatly. Ad
15、ditionally, if your database server is heavily loaded, while your web server isnt, you may also see very different results.Benchmarks are crap, for the most part. They dont really mean a whole lot, unless they represent the exact cases in which you will be using the functions being tested. However, in this case, they DO represent exactly what I will be doing.What does this mean? Inklog will no longer use the file system as its main method of data storage.
