jbox jaoo

jbox: 

jbox A Pure Java Cluster Node JAOO 2002 Michael Ringgaard (mringgaa@csc.com) Bjarne Hansen (bhansen4@csc.com)

Welcome & Agenda: 

Welcome & Agenda Welcome Bjarne Hansen, bhansen4@csc.com Computer Sciences Corporation Michael Ringgaard, mringgaa@csc.com Computer Sciences Corporation Agenda What is a jbox? Why would we want a jbox? What can a jbox be used for? How to build a jbox

What is a jbox?: 

What is a jbox? A server appliance for Java programs Requires only power and a network connection No monitor, keyboard, or mouse Built for standard Intel based PC Cheap, simple and powerful Runs only one process: the Java VM Specifically the HotSpot Java VM for Windows Relies on a small and efficient kernel Transforming application servers to appliances Java VM OS kernel J2SE, J2EE, ... Web applications

Appliances: 

Appliances Characteristics of appliances Unpack, connect, use... Can’t rely on experts to operate .. Must require just about zero maintenance Like: phone, TV, video, video game, washing machine, oven, ... Would be nice characteristics for an IT business system! By the way...next generation of home appliances: Broadband router, DHCP, DNS,...

Why a Java Appliance?: 

Why a Java Appliance? Need effective development and execution platform Hardware: Before: Exotic processor/hardware Now: Complies with PC specification Development platform Before: C, C like variant, or assembler Now: OO, VM, garbage collection Cost effective Extremely cheap hardware Develop on PC, execute on appliance Wide selection of development environments, tools, utilities... No specialized developers Java is a powerful and rich environment yet simple enough to use in an appliance

What can a jbox be used for?: 

What can a jbox be used for? What would we like to achieve? Apply the virtues of traditional appliances to IT business systems Apply the effective software development tools, utilities, and methodologies to appliance development As a Java server appliance Ideal development environment to develop, deploy and maintain software for appliances As a Java cluster node It’s better to own 100 appliances than 100 application servers

Just add water...: 

Web application Web application J2EE application Just add water... Ready in just 5 minutes!!!

Clusters of Appliances: 

Clusters of Appliances Clustering support is a feature of specific J2EE server products Focus on transparency (developer, user) Custom designed distributed architectures J2EE + Jini, JavaSpaces P2P, JXTA, ...

Appliance Management: 

Appliance Management Standalone appliances can be managed using browser interface Most J2EE servers has built-in web based management consoles Appliance clusters requires special attention on deployment and configuration issues How do you deploy applications to many nodes Centralized application and configuration repository (JMX). Manage applications, not servers

Application Clusters: 

Application Clusters

jbox – A Pure Java Cluster Node: 

jbox – A Pure Java Cluster Node How to build a jbox...

Java and the operating system: 

Java and the operating system What is actually going on under the hood when you run a Java application? How is the JVM using the operating system? What features of the operating system are used by a Java server application? Do you really need an operating system?

What is an operating system?: 

What is an operating system? Hardware Abstraction Layer Resource Manager Bootstrap Loader Application Programming Interface Virtual Machine Implementation Utility Collection One-stop-shopping User Entertainment System

Java VM on Windows: 

Java VM on Windows win32 kernel32.dll user32.dll wsock32.dll advapi32.dll msvcrt.dll winmm.dll Java VM jvm.dll java.dll net.dll zip.dll verify.dll hpi.dll java.exe Java application Windows

194 Windows API calls used: 

194 Windows API calls used KERNEL32 CloseHandle CreateEventA CreateFileA CreatePipe CreateProcessA CreateSemaphoreA DebugBreak DeleteFileA DisableThreadLibraryCalls DuplicateHandle EnterCriticalSection FindClose FindFirstFileA FindNextFileA FlushFileBuffers FormatMessageA FreeLibrary GetCurrentDirectoryA GetCurrentProcess GetCurrentThread GetCurrentThreadId GetEnvironmentVariableA GetExitCodeProcess GetFileAttributesA GetLastError GetLogicalDrives GetModuleFileNameA GetNumberOfConsoleInputEvents GetProcAddress GetStdHandle GetSystemDirectoryA GetSystemInfo GetSystemTime GetSystemTimeAsFileTime GetTempPathA GetThreadContext GetThreadLocale GetThreadPriority GetThreadTimes GetTimeZoneInformation GetVersionExA GetWindowsDirectoryA InitializeCriticalSection InterlockedDecrement InterlockedIncrement IsDBCSLeadByte LeaveCriticalSection LoadLibraryA PeekConsoleInputA PeekNamedPipe QueryPerformanceCounter QueryPerformanceFrequency ReleaseSemaphore RemoveDirectoryA ResetEvent ResumeThread SetConsoleCtrlHandler SetEndOfFile SetEvent SetFileAttributesA SetFilePointer SetFileTime SetHandleInformation SetThreadContext SetThreadPriority Sleep SuspendThread SystemTimeToFileTime TerminateProcess TlsAlloc TlsGetValue TlsSetValue VirtualAlloc VirtualFree VirtualQuery WaitForMultipleObjects WaitForSingleObject WideCharToMultiByte USER32 MessageBoxA ADVAPI32 GetUserNameA RegCloseKey RegEnumKeyExA RegOpenKeyExA RegQueryInfoKeyA RegQueryValueExA WSOCK32 __WSAFDIsSet accept bind closesocket connect gethostbyaddr gethostbyname gethostname getprotobyname getsockname getsockopt htonl htons ioctlsocket listen ntohl ntohs recv recvfrom select send sendto setsockopt shutdown socket WSACleanup WSAGetLastError WSAStartup MSVCRT new delete __dllonexit __mb_cur_max _access _adjust_fdiv _assert _beginthreadex _CIfmod _close _control87 _endthreadex _errno _except_handler3 _finite _fstati64 _ftol _fullpath _get_osfhandle _getdcwd _getdrive _initterm _iob _isctype _isnan _lseeki64 _mkdir _onexit _open _open_osfhandle _pctype _purecall _read _setjmp3 _setmode _stat _stati64 _strdup _vsnprintf _write abort atof calloc exit fclose fflush fgets fopen fprintf fputc free getc getenv isalnum isspace longjmp malloc memmove printf putchar qsort raise realloc rename signal sprintf sscanf strchr strerror strncmp strncpy strrchr strstr strtol toupper vfprintf vsprintf WINMM timeEndPeriod timeBeginPeriod timeGetTime

OS Services: 

OS Services file network virtual memory threads synchronization time resolver heap modules critical sections thread local storage Kernel context User context

JavaOS emulator: 

JavaOS emulator osexec.exe os.dll win32 process syscall mod heap stubs ... win32 emulation kernel32 user32 wsock32 advapi32 msvcrt winmm Java VM jvm java net zip verify hpi Java object heap Java classes ...

Design objectives: 

Design objectives Build a kernel for executing Java server application on appliances Use existing HotSpot VM Small,simple, fast but complete kernel Run on standard PC hardware (IA-32) Develop using Microsoft Visual C Use standard PE (EXE/DLL) executables

How to build a JavaOS kernel: 

How to build a JavaOS kernel Use the existing HotSpot VM Write stub DLLs for Win32 DLL Implement user mode components: loader, heap, tls, critsect, resolver... Implement a boot loader to load kernel Implement kernel memory management, thread control, device I/O and networking.

Core kernel services: 

Core kernel services System booting and application loading Memory Management Virtual memory mapping Physical memory allocation and paging Heap allocation and module loading and linking Thread Control Thread scheduling and trap handling Thread context Thread synchronization and timers I/O Management I/O bus and unit enumeration Block devices and file systems Stream devices Packet devices (NIC) and networking (TCP/IP)

OS Development on the Internet: 

OS Development on the Internet There are lots of information and code on the internet on OS topics: Linux kernel code (www.kernel.org) IA-32 Reference Manual (www.intel.com) TCBs and u-kernels (Jochen Liedtke, i30www.ira.uka.de/teaching/coursedocuments/47/) DNS Resolver (ISC BIND lwres, www.isc.org) TCP/IP Stack (Adam Dunkels, www.sics.se/~adam/lwip/) Heap Allocator (Doug Lea, http://gee.cs.oswego.edu/dl/html/malloc.html) Bochs (bochs.sourceforge.net) and WMWare simulators (www.vmware.com) IDE Disks (Hale Landis, www.ata-atapi.com) ...

Architecture layers: 

Architecture layers krnl.dll Java server application (e.g. tomcat, jboss) os.dll kernel win32 kernel32.dll user32.dll advapi.dll wsock32.dll winmm.dll msvcrt.dll jinit.exe jvm hpi.dll net.dll zip.dll jvm.dll java.dll verify.dll Java 2 SDK (rt.jar, tools.jar) app sdk boot osldr.dll boot

sanos API: 

sanos API canonicalize chdir chsize close dup flush format fstat fstatfs futime getcwd getfsstat ioctl link lseek mkdir mount open opendir read readdir readv rename rmdir stat statfs tell umount unlink utime write writev file accept bind connect getpeername getsockname getsockopt listen recv recvfrom send sendto setsockopt shutdown socket socket beginthread endthread epulse ereset eset getcontext getprio gettib gettid mkevent mksem resume self semrel setcontext setprio sleep suspend wait waitall waitany thread csfree enter leave mkcs critsect tlsalloc tlsfree tlsget tlsset tls calloc free mallinfo malloc realloc heap dn_comp dn_expand res_mkquery res_query res_querydomain res_search res_send resolver gethostbyaddr gethostbyname gethostname getprotobyname getprotobynumber getservbyname getservbyport inet_addr inet_ntoa netdb exec getmodpath getmodule load resolve unload module clock gettimeofday settimeofday time time mlock mmap mprotect mremap munlock munmap memory config dbgbreak exit loglevel panic peb syscall syslog system

Where is the code?: 

Where is the code? KLOC = Kilo Lines Of Code sanos kernel (40 KLOC) 2% HotSpot VM (235 KLOC) 12% J2SE Native (415 KLOC) 21% J2SE Java (1277 KLOC) 65%

Conclusion: 

Conclusion Is Java an operating system ? No, but if you add 2% to the code that is already there it can become an operating system! Did we write our own operating system ? No, we only made the kernel, SUN did the remaining 98%! sanos has been released as open source (BSD license) and is available for download at www.jbox.dk