用Varnish和Memcached給WordPress網站提速

2024-09-07 00:53:02

字體：大中小

來源：轉載

供稿：網友

Varnish是一款高性能的緩存加速器，Varnish把數據存放在服務器的內存中，利用內存可以極大的提高PHP頁面執行速度，可以設置0～60秒的精確緩存時間，32位的機器支持的緩存文件最大為2GB。

Varnish采用VCL的配置，而且具有強大的管理功能，如top、stat、admin、lis，管理方式比較靈活。Varnish的狀態機設計不僅巧妙，結構也很清晰，利用二叉堆管理緩存文件，即可達到隨時刪除的目的。

Memcached是一個高性能的分布式內存對象緩存系統，通過在內存中緩存數據和對象來減少讀取數據庫的次數，從而提高動態、數據庫驅動的速度。Memcached對于減少MysqL數據查詢壓力非常有幫助。

由于Varnish采用了VisualPageCache技術，所有緩存的數據都直接從內存讀取，而Squid從硬盤讀取緩存的數據，所以Varnish在訪問速度方面會更快一些。但是Varnish在高并發狀態下，CPU、IO和內存等資源的開銷高于Squid。

目前Varnish3.0版本解決了服務器重啟后Varnish緩存消失的問題，性能優化上有了更大的提升。本篇就來分享一下利用Varnish和Memcached緩存來給Wordpress加速，因為要用到內存，所以比較適合那些大內存的服務器。

用Varnish和Memcached緩存給Wordpress提速內存級加速

一、Varnish安裝方法

1、Varnish

varnishcache

2、對于Centos5的，可以執行以下命令來安裝

rpmnosignatureirepo.varnishcacheredhatvarnish3.0el5noarchvarnishreleasevarnishrelease3.01.el5.centos.noarch.rpm

yuminstallvarnish

3、對于是Centos6的，可以執行以下命令來安裝

rpmnosignatureirepo.varnishcacheredhatvarnish3.0el6noarchvarnishreleasevarnishrelease3.01.el6.noarch.rpm

yuminstallvarnish

4、如果版本搞錯，就會出現如下提示錯誤

error:Faileddependencies:

rpmlibFileDigests=4.6.01isneededbyvarnishrelease3.01.el6.noarch

rpmlibPayloadIsXz=5.21isneededbyvarnishrelease3.01.el6.noarch

:MissingDependency:libedit.so.0isneededbypackagevarnish3.0.51.el5.centos.i386varnish3.0

5、Centos5安裝時還會提示有依賴關系不能解決，解決的辦法就是添加擴展的YUM源，執行以下命令

rpmivhapt.sw.beredhatel5eni386rpmforgeRPMSrpmforgerelease0.5.11.el5.rf.i386.rpm32位

rpmivhapt.sw.beredhatel5enx86_64rpmforgeRPMSrpmforgerelease0.5.22.el5.rf.x86_64.rpm64位

yumcleanallyumupdate

6、對于是Debian系統，可以執行以下命令來安裝

curlrepo.varnishcachedebianGPGkey.txt|aptkeyaddecho"debrepo.varnishcachedebianwheezyvarnish3.0"etcaptsources.list

aptgetupdate

aptgetinstallvarnish

7、對于是Ubuntu系統，可以執行以下命令來安裝

curlrepo.varnishcachedebianGPGkey.txt|sudoaptkeyaddecho"debrepo.varnishcacheubuntuprecisevarnish3.0"|sudoteeaetcaptsources.listsudo

aptgetupdatesudo

aptgetinstallvarnish

8、設置Varnish開機啟動，執行 chkconfigvarnishon和chkconfigvarnishncsaon

9、啟動Varnish的命令是 servicevarnishstart和servicevarnishncsastart

二、Varnish相關配置

1、設置好Varnish緩存規則。默認是etcvarnishdefault.vcl，大家可以下載這個VarnishWordPress配置文件覆蓋原來的， centos.googlecodefilesdefault.vcl。源碼內容

#ThisisabasicVCLconfigurationfileforvarnish.Seethevcl7#manpagefordetailsonVCLsyntaxandsemantics.#Defaultbackenddefinition.Setthistopointtoyourcontent#server.backenddefault{.host="127.0.0.1";.port="8080";}aclpurge{"localhost";"127.0.0.1";}#BelowisacommentedoutcopyofthedefaultVCLlogic.Ifyou#redefineanyofthesesubroutines,thebuiltinlogicwillbe#appendedtoyourcode.subvcl_recv{#Onlycachethefollowingsiteifreq.http.host~"amhg.freehao123.info"{setreq.backend=default;}else{returnpass;}ifreq.request=="PURGE"{if!client.ip~purge{error405"Notallowed.";}returnlookup;}ifreq.restarts==0{ifreq.http.xforwardedfor{setreq.http.XForwardedFor=req.http.XForwardedFor+","+client.ip;}else{setreq.http.XForwardedFor=client.ip;}}ifreq.request!="GET"req.request!="HEAD"req.request!="PUT"req.request!="POST"req.request!="TRACE"req.request!="OPTIONS"req.request!="DELETE"{ NonRFC2616orCONNECTwhichisweird. returnpipe;}ifreq.request!="GET"req.request!="HEAD"{ WeonlydealwithGETandHEADbydefault returnpass;}ifreq.http.Authorization||req.http.Cookie~"wordpress_logged"||req.http.Cookie~"comment_"{ Notcacheablebydefault returnpass;}returnlookup;}subvcl_pipe{#Notethatonlythefirstrequesttothebackendwillhave#XForwardedForset.IfyouuseXForwardedForandwantto#haveitsetforallrequests,makesuretohave:#setbereq.http.connection="close";#here.Itisnotsetbydefaultasitmightbreaksomebrokenweb#applications,likeIISwithNTLMauthentication.returnpipe;}subvcl_pass{returnpass;}subvcl_hash{hash_datareq.url;ifreq.http.host{hash_datareq.http.host;}else{hash_dataserver.ip;}returnhash;}subvcl_hit{ifreq.request=="PURGE"{purge;error200"Purged.";}returndeliver;}subvcl_miss{ifreq.request=="PURGE"{purge;error200"Purged.";}returnfetch;}subvcl_fetch{ifberesp.ttl=0s||beresp.http.SetCookie||beresp.http.Vary==" "{ Markas"HitForPass"forthenext2minutes setberesp.ttl=120s;returnhit_for_pass;}setberesp.ttl=1d;returndeliver;}subvcl_deliver{returndeliver;}subvcl_error{setobj.http.ContentType="texthtml;charset=utf8";setobj.http.RetryAfter="5";synthetic{"?xmlversion="1.0"encoding="utf8"?!DOCTYPEhtmlPUBLIC"W3CDTDXHTML1.0StrictEN""w3TRxhtml1DTDxhtml1strict.dtd"htmlheadtitle"}+obj.status+""+obj.response+{"titleheadbodyError"}+obj.status+""+obj.response+{"h1"}+obj.response+{"GuruMeditation:h3XID:"}+req.xid+{"Varnishcacheserverbodyhtml"};returndeliver;}subvcl_init{returnok;}subvcl_fini{returnok;}