PostgreSQL的磁盘空间占用问题

　　Asaneasyperformanceboostwithnodownside,makesurethefilesystemonwhichyourdatabaseiskeptismounted"noatime",whichturnsofftheaccesstimebookkeeping.　

　　4.2TrytheAutoVacuumdaemon

　　ThereisalittleknownmoduleinPostgreSQLcontribdirectorycalledaspgavd.Itworksinconjunctionwithstatisticscollector.Itperiodicallyconnectstoadatabaseandchecksifithasdoneenoughoperationssincethelastcheck.Ifyes,itwillvacuumthedatabase.　

　　Essentiallyitwillvacuumthedatabasewhenitneedsit.Itwouldgetridofplayingwithcronsettingsforvacuumfrequency.Itshouldresultinbetterdatabaseperformancebyeliminatingoverduevacuumissues.　

　　4.3TryFreeBSD

　　Largeupdates,deletes,andvacuuminPostgreSQLareverydiskintensiveprocesses.Inparticular,sincevacuumgobblesupIObandwidth,therestofthedatabaseactivitiescouldbeaffectedadverselywhenvacuumingverylargetables.　

　　OS'sfromtheBSDfamily,suchasFreeBSD,dynamicallyaltertheIOpriorityofaprocess.Soifyoulowerthepriorityofavacuumprocess,itshouldnotchewasmuchbandwidthandwillbetterallowthedatabasetoperformnormally.Ofcoursethismeansthatvacuumcouldtakelonger,whichwouldbeproblematicfora"vacuumfull."　

　　IfyouarenotdonewithyourchoiceofOSforyourserverplatform,considerBSDforthisreason.　

　　5TheCONFSettingGuide

　　AvailablehereisanAnnotatedGuidetothePostgreSQLconfigurationfilesettings,inbothOpenOffice.organdPDFformat.Thisguideexpandsontheofficialdocumentationandmayeventuallybeincorporatedintoit.