Java several useful commands-all Options, Memory Options, GC options, System Properties, Thread dump, Heap dump

• Jcmd # #Refer to http://www.cnblogs.com/tang88seng/p/4497725.html
• Java -xx:+printflagsfinal -version #Display all JVM options
• Java -xx:+printcommandlineflags -version # #Display default JVM Memory and GC options

-xx:initialheapsize=134209344 -xx:maxheapsize=2147349504 -xx:+printcommandlineflags-xx:+ usecompressedclasspointers-xx:+usecompressedoops-xx:-uselargepagesindividualallocation-xx:+" 1.8.0_60 "  1.8. 0_60-25.60-b23, Mixed mode)

• Java-xshowsettings # #Display System Properties

Java- xshowsettingsVM Settings:max. Heap Size (estimated):1. 05G Ergonomics Machine Class:server Using Vm:java HotSpot (TM) --Bit Server VM Propertysettings: awt.toolkit=Sun.awt.X11.XToolkit file.encoding= utf-8file.encoding.pkg=Sun.io File.separator= /java.awt.graphicsenv=sun.awt.X11GraphicsEnvironment java.awt.printerjob=sun.print.PSPrinterJob java.class. Path =/xxxxxjava.class. Version =51.0Java.endorsed.dirs=/ptc/windchill_10.2/java/jre/lib/endorsed Java.ext.dirs=/ptc/windchill_10.2/java/jre/lib/ext/usr/java/packages/lib/ext java.home=/ptc/windchill_10.2/java/JRE Java.io.tmpdir= /tmp Java.library.path=/usr/java/packages/lib/AMD64/usr/lib64/lib64/Lib/usr/Lib Java.runtime.name=Java (TM) SE Runtime Environment Java.runtime.version=1.7.0_72-B14 Java.specification.name=Java Platform API specification Java.specification.vendor=Oracle Corporation java.specification.version=1.7Java.vendor=Oracle Corporation Java.vendor.url= http://java.oracle.com/Java.vendor.url.bug = http://bugreport.sun.com/bugreport/Java.version =1.7. 0_72 Java.vm.info=Mixed Mode Java.vm.name= Java HotSpot (TM) --Bit Server VM java.vm.specification.name=Java Virtual Machine specification Java.vm.specification.vendor=Oracle Corporation java.vm.specification.version=1.7Java.vm.vendor=Oracle Corporation java.vm.version=24.72-b04 Line.separator=\ Os.arch=AMD64 os.name=Linux os.version=2.6. --371.8.1. El5 Path.separator=: Sun.arch.data.model= -Sun.boot.class. Path =/ptc/windchill_10.2/java/jre/lib/Resources.jar/ptc/windchill_10.2/java/jre/lib/Rt.jar/ptc/windchill_10.2/java/jre/lib/Sunrsasign.jar/ptc/windchill_10.2/java/jre/lib/Jsse.jar/ptc/windchill_10.2/java/jre/lib/Jce.jar/ptc/windchill_10.2/java/jre/lib/Charsets.jar/ptc/windchill_10.2/java/jre/lib/Jfr.jar/ptc/windchill_10.2/java/jre/Classes Sun.boot.library.path=/ptc/windchill_10.2/java/jre/lib/AMD64 Sun.cpu.endian=Little Sun.cpu.isalist=Sun.desktop=Gnome Sun.io.unicode.encoding=Unicodelittle Sun.java.launcher=Sun_standard sun.jnu.encoding= utf-8Sun.management.compiler= HotSpot --Bit tiered Compilers sun.os.patch.level=Unknown User.country=US User.dir=/ptc/windchill_10.2/windchill/codebase/wt/workflow/Expr User.home=/home/wcadmin user.language=en user.name=wcadmin User.timezone=Locale Settings:defaultLocale =中文版defaultDisplay locale =中文版 (states)defaultFormat locale =中文版 (states) available locales=ar, Ar_ae, Ar_bh, Ar_dz, Ar_eg, Ar_iq, Ar_jo, ar_kw, ar_lb, Ar_ly, Ar_ma, Ar_om, Ar_qa, Ar_sa, AR_SD, Ar_sy, Ar_tn, Ar_ye, be, be_by, BG, BG_BG, CA, Ca_es, CS, Cs_cz, DA, Da_dk, DE, De_at, De_ch, De_de, de_l U, El, El_cy, El_gr, en, En_au, En_ca, EN_GB, En_ie, en_in, EN_MT, En_nz, En_ph, En_sg, en_US, En_za, ES, Es_ar, Es_bo, ES_CL, Es_co, ES_CR, Es_do, Es_ec, Es_es, Es_gt, Es_hn, Es_mx, Es_ni, Es_pa, Es_pe, ES_PR, E S_py, ES_SV, Es_us, Es_uy, Es_ve, ET, Et_ee, FI, Fi_fi, FR, Fr_be, Fr_ca, Fr_ch, Fr_fr, Fr_lu, GA, Ga_ie, hi_in, HR, hr_hr, Hu, Hu_hu,inch, in_id, is, Is_is, it, It_ch, It_it, IW, Iw_il, JA, JA_JP, ja_jp_jp_#u-ca-Japanese, Ko, Ko_kr, lt, lt_lt, LV, LV_LV, MK, MK_MK, MS, Ms_my, MT, MT_MT, NL, Nl_be, Nl_nl, no, no_n O, no_no_ny, PL, Pl_pl, PT, PT_BR, Pt_pt, Ro, Ro_ro, Ru, Ru_ru, SK, Sk_sk, SL, sl_si, SQ, Sq_al, Sr, Sr_ba , Sr_ba_#latn, Sr_cs, Sr_me, Sr_me_#latn, Sr_rs, Sr_rs_#latn, Sr__#latn, SV, sv_se, Th, th_th, th_th_th_#u -nu-Thai, TR, TR_TR, UK, Uk_ua, VI, VI_VN, en, ZH_CN, ZH_HK, Zh_sg, ZH_TW

Java several useful commands-all Options, Memory Options, GC options, System Properties, Thread dump, Heap dump