<?xml version="1.0" encoding="iso-8859-1"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title>Class: CacheManager</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <meta http-equiv="Content-Script-Type" content="text/javascript" /> <link rel="stylesheet" href=".././rdoc-style.css" type="text/css" media="screen" /> <script type="text/javascript"> // <![CDATA[ function popupCode( url ) { window.open(url, "Code", "resizable=yes,scrollbars=yes,toolbar=no,status=no,height=150,width=400") } function toggleCode( id ) { if ( document.getElementById ) elem = document.getElementById( id ); else if ( document.all ) elem = eval( "document.all." + id ); else return false; elemStyle = elem.style; if ( elemStyle.display != "block" ) { elemStyle.display = "block" } else { elemStyle.display = "none" } return true; } // Make codeblocks hidden by default document.writeln( "<style type=\"text/css\">div.method-source-code { display: none }</style>" ) // ]]> </script> </head> <body> <div id="classHeader"> <table class="header-table"> <tr class="top-aligned-row"> <td><strong>Class</strong></td> <td class="class-name-in-header">CacheManager</td> </tr> <tr class="top-aligned-row"> <td><strong>In:</strong></td> <td> <a href="../files/lib/storage/cache_rb.html"> lib/storage/cache.rb </a> <br /> </td> </tr> <tr class="top-aligned-row"> <td><strong>Parent:</strong></td> <td> Object </td> </tr> </table> </div> <!-- banner header --> <div id="bodyContent"> <div id="contextContent"> <div id="diagram"> <map id="map" name="map"> <area shape="rect" coords="5,5,96,53" href="CacheStats.html" alt="CacheStats " /> <area shape="rect" coords="120,5,232,53" href="CacheManager.html" alt="CacheManager " /> <area shape="rect" coords="256,5,347,53" href="CacheEntry.html" alt="CacheEntry " /> </map> <img src="../dot/f_42.png" usemap="#map" border="0" alt="dot/f_42.png"> </div> <div id="description"> <p> This class manages the cache. It is initialized by the <a href="Store.html">Store</a> and front ends the database behind the <a href="Store.html">Store</a>. </p> </div> </div> <div id="method-list"> <h3 class="section-bar">Methods</h3> <div class="name-list"> <a href="#M000131">delete</a> <a href="#M000129">get</a> <a href="#M000128">hash</a> <a href="#M000127">inspect</a> <a href="#M000137">keys</a> <a href="#M000135">makenoswap</a> <a href="#M000136">makeswap</a> <a href="#M000132">mark</a> <a href="#M000126">new</a> <a href="#M000130">put</a> <a href="#M000138">stats</a> <a href="#M000133">sync</a> <a href="#M000134">sync_chain</a> </div> </div> </div> <!-- if includes --> <div id="section"> <!-- if method_list --> <div id="methods"> <h3 class="section-bar">Public Class methods</h3> <div id="method-M000126" class="method-detail"> <a name="M000126"></a> <div class="method-heading"> <a href="#M000126" class="method-signature"> <span class="method-name">new</span><span class="method-args">(db)</span> </a> </div> <div class="method-description"> <p><a class="source-toggle" href="#" onclick="toggleCode('M000126-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000126-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 112</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">initialize</span>(<span class="ruby-identifier">db</span>) <span class="ruby-ivar">@cwidth</span> = <span class="ruby-identifier">options</span>[<span class="ruby-value str">'cache_width'</span>] <span class="ruby-ivar">@cdepth</span> = <span class="ruby-identifier">options</span>[<span class="ruby-value str">'cache_depth'</span>] <span class="ruby-ivar">@db</span> = <span class="ruby-identifier">db</span> <span class="ruby-ivar">@st</span> = <span class="ruby-constant">CacheStats</span>.<span class="ruby-identifier">new</span> <span class="ruby-ivar">@cache</span> = <span class="ruby-constant">Array</span>.<span class="ruby-identifier">new</span>(<span class="ruby-ivar">@cwidth</span>) {<span class="ruby-constant">Array</span>.<span class="ruby-identifier">new</span>} <span class="ruby-ivar">@cwidth</span>.<span class="ruby-identifier">times</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">i</span><span class="ruby-operator">|</span> <span class="ruby-ivar">@cdepth</span>.<span class="ruby-identifier">times</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">j</span><span class="ruby-operator">|</span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">i</span>] <span class="ruby-operator"><<</span> <span class="ruby-constant">CacheEntry</span>.<span class="ruby-identifier">new</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_size</span>) <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <h3 class="section-bar">Public Instance methods</h3> <div id="method-M000131" class="method-detail"> <a name="M000131"></a> <div class="method-heading"> <a href="#M000131" class="method-signature"> <span class="method-name">delete</span><span class="method-args">(oid)</span> </a> </div> <div class="method-description"> <p> <a href="CacheManager.html#M000131">delete</a> an object </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000131-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000131-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 254</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">delete</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">oid</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:deletes</span>) <span class="ruby-identifier">hv</span> = <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-comment cmt"># mark dead in cache </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">next</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-operator">!=</span> <span class="ruby-identifier">oid</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">mark_dead</span> <span class="ruby-keyword kw">break</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># delete it from the database </span> <span class="ruby-ivar">@db</span>.<span class="ruby-identifier">delete</span>(<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span>) <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000129" class="method-detail"> <a name="M000129"></a> <div class="method-heading"> <a href="#M000129" class="method-signature"> <span class="method-name">get</span><span class="method-args">(oid)</span> </a> </div> <div class="method-description"> <p> gets an object </p> <dl> <dt><tt>oid</tt></dt><dd>- integer object id to retrieve </dd> <dt><tt>return</tt></dt><dd>- a reference to the object or nil if none exists </dd> </dl> <p><a class="source-toggle" href="#" onclick="toggleCode('M000129-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000129-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 151</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">get</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">oid</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:reads</span>) <span class="ruby-identifier">hv</span> = <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-comment cmt"># search the cache </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-operator">==</span> <span class="ruby-identifier">oid</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_read_hits</span>) <span class="ruby-comment cmt"># need to try putting hot hit to the head of the list? </span> <span class="ruby-keyword kw">return</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">obj</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># cache miss - search the database </span> <span class="ruby-keyword kw">if</span> <span class="ruby-ivar">@db</span>.<span class="ruby-identifier">has_key?</span> <span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span> <span class="ruby-identifier">ret</span> = <span class="ruby-constant">Utility</span>.<span class="ruby-identifier">decode</span>(<span class="ruby-ivar">@db</span>[<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span>]) <span class="ruby-keyword kw">else</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:database_read_fails</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">end</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:database_reads</span>) <span class="ruby-comment cmt"># get and remove the last entry off this list </span> <span class="ruby-identifier">ch</span> = <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">pop</span> <span class="ruby-comment cmt"># if its dirty we write it to the database </span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">dirty?</span> <span class="ruby-operator">&&</span> <span class="ruby-operator">!</span><span class="ruby-identifier">ch</span>.<span class="ruby-identifier">dead?</span> <span class="ruby-ivar">@db</span>[<span class="ruby-identifier">ch</span>.<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span>] = <span class="ruby-constant">Utility</span>.<span class="ruby-identifier">encode</span>(<span class="ruby-identifier">ch</span>.<span class="ruby-identifier">obj</span>) <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:database_writes</span>) <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">noswap?</span> <span class="ruby-comment cmt"># here we have a problem we can't use this </span> <span class="ruby-comment cmt"># first push it back onto the list </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">unshift</span> <span class="ruby-identifier">ch</span> <span class="ruby-comment cmt"># get ourselves a brand new </span> <span class="ruby-identifier">ch</span> = <span class="ruby-constant">CacheEntry</span>.<span class="ruby-identifier">new</span> <span class="ruby-comment cmt"># problem solved </span> <span class="ruby-comment cmt"># the depth of any list chains will be cache_depth + # noswap entries </span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># assign our new object to the cache entry </span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">obj</span> = <span class="ruby-identifier">ret</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">oid</span> = <span class="ruby-identifier">oid</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">clean!</span> <span class="ruby-comment cmt"># push it to the head of the list </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">unshift</span> <span class="ruby-identifier">ch</span> <span class="ruby-identifier">ret</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000128" class="method-detail"> <a name="M000128"></a> <div class="method-heading"> <a href="#M000128" class="method-signature"> <span class="method-name">hash</span><span class="method-args">(oid)</span> </a> </div> <div class="method-description"> <p> Our simple <a href="CacheManager.html#M000128">hash</a> algoritm. Our database <a href="CacheManager.html#M000137">keys</a> are sequentially assigned integers, so… I don‘t know what would be better. </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000128-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000128-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 144</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-identifier">oid</span> <span class="ruby-operator">%</span> <span class="ruby-ivar">@cwidth</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000127" class="method-detail"> <a name="M000127"></a> <div class="method-heading"> <a href="#M000127" class="method-signature"> <span class="method-name">inspect</span><span class="method-args">()</span> </a> </div> <div class="method-description"> <p> report on the cache map see cmd_dumpcache </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000127-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000127-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 130</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">inspect</span> <span class="ruby-identifier">str</span> = <span class="ruby-node">"cache width:#{@cwidth} cache depth:#{@cdepth}\n"</span> <span class="ruby-ivar">@cwidth</span>.<span class="ruby-identifier">times</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">i</span><span class="ruby-operator">|</span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">i</span>].<span class="ruby-identifier">each_with_index</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span>,<span class="ruby-identifier">j</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">next</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">dead?</span> <span class="ruby-identifier">str</span> <span class="ruby-operator"><<</span> <span class="ruby-node">"cache map [#{i}][#{j}] => "</span> <span class="ruby-identifier">str</span> <span class="ruby-operator"><<</span> <span class="ruby-node">"oid #{ce.oid} object_id #{ce.obj.object_id} dirty? #{ce.dirty?} noswap? #{ce.noswap?}\n"</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-identifier">str</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000137" class="method-detail"> <a name="M000137"></a> <div class="method-heading"> <a href="#M000137" class="method-signature"> <span class="method-name">keys</span><span class="method-args">()</span> </a> </div> <div class="method-description"> <p> This is provided to traverse the entire object chain. This thrashes the cache violently. See <a href="Store.html#M000084">Store#each</a>. One needs to question the design of routines that use <a href="Store.html#M000084">Store#each</a> above. </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000137-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000137-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 359</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">keys</span> <span class="ruby-identifier">kys</span> = [] <span class="ruby-ivar">@cwidth</span>.<span class="ruby-identifier">times</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">i</span><span class="ruby-operator">|</span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">i</span>].<span class="ruby-identifier">each</span> {<span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-identifier">kys</span> <span class="ruby-operator"><<</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-keyword kw">if</span> <span class="ruby-operator">!</span><span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">nil?</span> } <span class="ruby-keyword kw">end</span> <span class="ruby-identifier">kys</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000135" class="method-detail"> <a name="M000135"></a> <div class="method-heading"> <a href="#M000135" class="method-signature"> <span class="method-name">makenoswap</span><span class="method-args">(oid)</span> </a> </div> <div class="method-description"> <p> Mark an object in the cache as nonswappable </p> <dl> <dt><tt>oid</tt></dt><dd>is the object id </dd> <dt><tt>return</tt></dt><dd>undefined </dd> </dl> <p><a class="source-toggle" href="#" onclick="toggleCode('M000135-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000135-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 319</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">makenoswap</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">oid</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_noswap</span>) <span class="ruby-identifier">hv</span> = <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">next</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-operator">!=</span> <span class="ruby-identifier">oid</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">noswap!</span> <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># This would indicate we've tried marking it noswap before we did a put. </span> <span class="ruby-comment cmt"># A logic error </span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_noswap_misses</span>) <span class="ruby-identifier">log</span>.<span class="ruby-identifier">debug</span> <span class="ruby-node">"Marking object nonswappable before put - #{oid}"</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000136" class="method-detail"> <a name="M000136"></a> <div class="method-heading"> <a href="#M000136" class="method-signature"> <span class="method-name">makeswap</span><span class="method-args">(oid)</span> </a> </div> <div class="method-description"> <p> Mark an object in the cache as swappable </p> <dl> <dt><tt>oid</tt></dt><dd>is the object id </dd> <dt><tt>return</tt></dt><dd>undefined </dd> </dl> <p><a class="source-toggle" href="#" onclick="toggleCode('M000136-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000136-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 339</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">makeswap</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">oid</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_swap</span>) <span class="ruby-identifier">hv</span> = <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">next</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-operator">!=</span> <span class="ruby-identifier">oid</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">swap!</span> <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># This would indicate we've tried marking it swap before we did a put. </span> <span class="ruby-comment cmt"># A logic error </span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_swap_misses</span>) <span class="ruby-identifier">log</span>.<span class="ruby-identifier">debug</span> <span class="ruby-node">"Marking object swappable before put - #{oid}"</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000132" class="method-detail"> <a name="M000132"></a> <div class="method-heading"> <a href="#M000132" class="method-signature"> <span class="method-name">mark</span><span class="method-args">(oid)</span> </a> </div> <div class="method-description"> <p> deliberately <a href="CacheManager.html#M000132">mark</a> an object in the cache as dirty see properties. </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000132-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000132-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 271</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">mark</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">oid</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_marks</span>) <span class="ruby-identifier">hv</span> = <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">oid</span>) <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">next</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-operator">!=</span> <span class="ruby-identifier">oid</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">dirty!</span> <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># this would indicate we've tried marking it dirty before we did a put. </span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_mark_misses</span>) <span class="ruby-identifier">log</span>.<span class="ruby-identifier">debug</span> <span class="ruby-node">"Marking object dirty before put - #{oid}"</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000130" class="method-detail"> <a name="M000130"></a> <div class="method-heading"> <a href="#M000130" class="method-signature"> <span class="method-name">put</span><span class="method-args">(obj)</span> </a> </div> <div class="method-description"> <p> puts an object </p> <dl> <dt><tt>obj</tt></dt><dd>- The integer object id to retrieve </dd> <dt><tt>return</tt></dt><dd>- undefined </dd> </dl> <p><a class="source-toggle" href="#" onclick="toggleCode('M000130-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000130-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 203</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">put</span>(<span class="ruby-identifier">obj</span>) <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">nil</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">obj</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:writes</span>) <span class="ruby-identifier">hv</span> = <span class="ruby-identifier">hash</span>(<span class="ruby-identifier">obj</span>.<span class="ruby-identifier">id</span>) <span class="ruby-comment cmt"># search the cache </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">next</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span> <span class="ruby-operator">!=</span> <span class="ruby-identifier">obj</span>.<span class="ruby-identifier">id</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_write_hits</span>) <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">dirty?</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">obj</span>.<span class="ruby-identifier">object_id</span> <span class="ruby-operator">!=</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">obj</span>.<span class="ruby-identifier">object_id</span> <span class="ruby-comment cmt"># be safe </span> <span class="ruby-comment cmt"># Be extra careful here. It's possible we could have two objects </span> <span class="ruby-comment cmt"># with the same object id but with different Ruby object_ids. </span> <span class="ruby-comment cmt"># Most likely this is a bug, but we should handle it here.. </span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">obj</span> = <span class="ruby-identifier">obj</span> <span class="ruby-identifier">log</span>.<span class="ruby-identifier">warn</span> <span class="ruby-value str">"Duplicate object id's in cache!"</span> <span class="ruby-identifier">log</span>.<span class="ruby-identifier">warn</span> <span class="ruby-node">"insert - #{obj.inspect}"</span> <span class="ruby-identifier">log</span>.<span class="ruby-identifier">warn</span> <span class="ruby-node">"cache - #{obj.inspect}"</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># need to try putting hot hit to the head of the list? </span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">dirty!</span> <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># get and remove the last entry off this list </span> <span class="ruby-identifier">ch</span> = <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">pop</span> <span class="ruby-comment cmt"># if its dirty we write it to the database </span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">dirty?</span> <span class="ruby-operator">&&</span> <span class="ruby-operator">!</span><span class="ruby-identifier">ch</span>.<span class="ruby-identifier">dead?</span> <span class="ruby-comment cmt"># errors possible - check in store module </span> <span class="ruby-ivar">@db</span>[<span class="ruby-identifier">ch</span>.<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span>] = <span class="ruby-constant">Utility</span>.<span class="ruby-identifier">encode</span>(<span class="ruby-identifier">ch</span>.<span class="ruby-identifier">obj</span>) <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:database_writes</span>) <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">noswap?</span> <span class="ruby-comment cmt"># here we have a problem we can't use this </span> <span class="ruby-comment cmt"># first push it back onto the list </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">unshift</span> <span class="ruby-identifier">ch</span> <span class="ruby-comment cmt"># get ourselves a brand new </span> <span class="ruby-identifier">ch</span> = <span class="ruby-constant">CacheEntry</span>.<span class="ruby-identifier">new</span> <span class="ruby-comment cmt"># problem solved </span> <span class="ruby-comment cmt"># the depth of any list chains will be cache_depth + # noswap entries </span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-comment cmt"># assign our new object to the cache entry </span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">obj</span> = <span class="ruby-identifier">obj</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">oid</span> = <span class="ruby-identifier">obj</span>.<span class="ruby-identifier">id</span> <span class="ruby-identifier">ch</span>.<span class="ruby-identifier">dirty!</span> <span class="ruby-comment cmt"># push it to the head of the list </span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">hv</span>].<span class="ruby-identifier">unshift</span> <span class="ruby-identifier">ch</span> <span class="ruby-keyword kw">return</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000138" class="method-detail"> <a name="M000138"></a> <div class="method-heading"> <a href="#M000138" class="method-signature"> <span class="method-name">stats</span><span class="method-args">()</span> </a> </div> <div class="method-description"> <p> produce a report - see cmd_stats </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000138-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000138-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 368</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">stats</span> <span class="ruby-identifier">str</span> = <span class="ruby-value str">"----------* Cache Statistics *----------\n"</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">k</span>,<span class="ruby-identifier">v</span><span class="ruby-operator">|</span> <span class="ruby-identifier">str</span> <span class="ruby-operator"><<</span> <span class="ruby-identifier">sprintf</span>(<span class="ruby-value str">"%25-25s : %d\n"</span>,<span class="ruby-identifier">k</span>.<span class="ruby-identifier">to_s</span>.<span class="ruby-identifier">gsub</span>(<span class="ruby-regexp re">/_/</span>,<span class="ruby-value str">' '</span>),<span class="ruby-identifier">v</span>) <span class="ruby-keyword kw">end</span> <span class="ruby-identifier">str</span> <span class="ruby-operator"><<</span> <span class="ruby-value str">"----------* *----------\n"</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000133" class="method-detail"> <a name="M000133"></a> <div class="method-heading"> <a href="#M000133" class="method-signature"> <span class="method-name">sync</span><span class="method-args">()</span> </a> </div> <div class="method-description"> <p> syncronize the entire cache with the database called by save. </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000133-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000133-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 289</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">sync</span> <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:cache_syncs</span>) <span class="ruby-comment cmt"># search the list chains for dirty objects and write them out. </span> <span class="ruby-ivar">@cwidth</span>.<span class="ruby-identifier">times</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">i</span><span class="ruby-operator">|</span> <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">i</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">dirty?</span> <span class="ruby-ivar">@db</span>[<span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span>] = <span class="ruby-constant">Utility</span>.<span class="ruby-identifier">encode</span>(<span class="ruby-identifier">ce</span>.<span class="ruby-identifier">obj</span>) <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:database_writes</span>) <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">clean!</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> <div id="method-M000134" class="method-detail"> <a name="M000134"></a> <div class="method-heading"> <a href="#M000134" class="method-signature"> <span class="method-name">sync_chain</span><span class="method-args">(i)</span> </a> </div> <div class="method-description"> <p> syncronize a specific list chain not yet called but included for possible performance enhancement </p> <p><a class="source-toggle" href="#" onclick="toggleCode('M000134-source');return false;">[Source]</a></p> <div class="method-source-code" id="M000134-source"> <pre> <span class="ruby-comment cmt"># File lib/storage/cache.rb, line 305</span> <span class="ruby-keyword kw">def</span> <span class="ruby-identifier">sync_chain</span>(<span class="ruby-identifier">i</span>) <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:chain_syncs</span>) <span class="ruby-ivar">@cache</span>[<span class="ruby-identifier">i</span>].<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">ce</span><span class="ruby-operator">|</span> <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">dirty?</span> <span class="ruby-ivar">@db</span>[<span class="ruby-identifier">ce</span>.<span class="ruby-identifier">oid</span>.<span class="ruby-identifier">to_s</span>] = <span class="ruby-constant">Utility</span>.<span class="ruby-identifier">encode</span>(<span class="ruby-identifier">ce</span>.<span class="ruby-identifier">obj</span>) <span class="ruby-ivar">@st</span>.<span class="ruby-identifier">inc</span>(<span class="ruby-identifier">:database_writes</span>) <span class="ruby-identifier">ce</span>.<span class="ruby-identifier">clean!</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> <span class="ruby-keyword kw">end</span> </pre> </div> </div> </div> </div> </div> <div id="validator-badges"> <p><small><a href="http://validator.w3.org/check/referer">[Validate]</a></small></p> </div> </body> </html>