system revision 1.8
1 1.8 agc $NetBSD: system,v 1.8 2009/11/17 21:09:54 agc Exp $ 2 1.1 agc 3 1.1 agc NetBSD System Roadmap 4 1.2 jmmv ===================== 5 1.1 agc 6 1.1 agc This is a small roadmap document, and deals with the main system 7 1.1 agc aspects of the operating system. 8 1.1 agc 9 1.8 agc The following projects are already in NetBSD-current and will appear 10 1.8 agc in NetBSD 6.0: 11 1.1 agc 12 1.6 agc 1. 64-bit time values supported 13 1.6 agc 2. Better Kernel Modules support 14 1.8 agc 5. namei() tactical changes 15 1.8 agc 10. emap (ephemeral mapping) support for i386 and amd64 16 1.8 agc 11. support for mDNSResponder 17 1.8 agc 18 1.8 agc The following projects are expected to be included in NetBSD 6.0 19 1.8 agc 20 1.6 agc 3. Full kernel preemption for real-time threads 21 1.6 agc 4. POSIX shared memory 22 1.6 agc 6. Better resource controls 23 1.6 agc 7. Improved observability: online crashdumps, remote debugging 24 1.6 agc 8. Processor and cache topology aware scheduler 25 1.6 agc 9. namei() strategic changes 26 1.1 agc 27 1.6 agc We currently expect to branch 6.0 in the March 2010 timeframe, with a view 28 1.6 agc to a 6.0 release later in 2010. 29 1.1 agc 30 1.1 agc We'll continue to update this roadmap as features and dates get firmed up. 31 1.1 agc 32 1.1 agc 33 1.1 agc Some explanations 34 1.1 agc ================= 35 1.1 agc 36 1.6 agc 1. 64-bit time_t support 37 1.1 agc ------------------------- 38 1.1 agc 39 1.1 agc The Unix 32-bit time_t value will overflow in 2037 - any mortgage calculations 40 1.1 agc which use a time_t value are in danger of overflowing at the present time - 41 1.1 agc and to address this, 64-bit time_t values will be used to contain the number 42 1.7 agc of seconds since 1970. This was completed in 5.99.7 by Christos (with no libc 43 1.7 agc major bump - kudos and respect), and will be in 6.0. 44 1.1 agc 45 1.1 agc Responsible: christos 46 1.1 agc 47 1.6 agc 2. Better Kernel Module Support 48 1.6 agc ------------------------------- 49 1.6 agc 50 1.6 agc Starting with 5.99.2, the kernel support for modules was enhanced by 51 1.6 agc ad, and GENERIC was switched over to be a MODULAR kernel. Support 52 1.6 agc from booting from modules, like ffs, was introduced at the same time. 53 1.6 agc Some work has been done by Luke Mewburn in this area to define module 54 1.6 agc locations and paths so that effective kernel development can be done 55 1.8 agc using modules. Kernel modules have been moved out of base.tgz and a new 56 1.8 agc modules.tgz has been created. 57 1.6 agc 58 1.6 agc Responsible: ad, lukem 59 1.6 agc 60 1.7 agc 3. Full kernel preemption for real-time threads on non-x86 61 1.7 agc ---------------------------------------------------------- 62 1.5 agc 63 1.7 agc With the revamp of the kernel concurrency model, much of the kernel is 64 1.7 agc fully multi-threaded and can therefore be preempted at any time. In 65 1.7 agc support of lower context switch and dispatch times for real-time 66 1.7 agc threads, full kernel preemption is being implemented. This has been 67 1.7 agc implemented already for i386 and x86_64 (and is in 5.0), but needs to 68 1.7 agc be extended to support the ARM, MIPS and SuperH ports. 69 1.7 agc 70 1.7 agc Responsible: rmind 71 1.5 agc 72 1.6 agc 4. POSIX shared memory 73 1.6 agc ---------------------- 74 1.1 agc 75 1.1 agc Implement POSIX shared memory facilities, which can be used to create the 76 1.1 agc shared memory objects and add the memory locations to the address space of 77 1.1 agc a process. 78 1.1 agc 79 1.1 agc Responsible: rmind 80 1.1 agc 81 1.6 agc 5. Incremental namei improvements, Phase 1 82 1.6 agc ------------------------------------------ 83 1.1 agc 84 1.6 agc In NetBSD 5.99.15, some changes were made to split the namei() routine 85 1.6 agc up into logical parts, so that changes can be made to the constituent 86 1.7 agc parts in a less intrusive way. This is in the repository now, and will 87 1.7 agc be in 6.0. 88 1.1 agc 89 1.1 agc Responsible: dholland 90 1.1 agc 91 1.6 agc 6. Better resource controls 92 1.6 agc --------------------------- 93 1.1 agc 94 1.1 agc A resource provisioning and control framework that extends beyond the 95 1.1 agc traditional Unix process limits. 96 1.1 agc 97 1.6 agc 7. Improved observability: online crashdumps, remote debugging 98 1.6 agc -------------------------------------------------------------- 99 1.1 agc 100 1.1 agc XXX crashdumps while the system is running 101 1.1 agc XXX firewire support in libkvm 102 1.1 agc 103 1.6 agc 8. Processor and cache topology aware scheduler 104 1.6 agc ----------------------------------------------- 105 1.1 agc 106 1.1 agc Implement the detection of the topology of the processors and caches. 107 1.1 agc Improve the scheduler to make decisions about thread migration 108 1.1 agc according to the topology, to get better thread affinity and less 109 1.1 agc cache thrashing, and thus improve overall performance in modern SMP 110 1.1 agc systems. 111 1.1 agc 112 1.1 agc Responsible: rmind 113 1.1 agc 114 1.6 agc 9. Incremental namei improvements, Phase 2 115 1.6 agc ------------------------------------------ 116 1.1 agc 117 1.7 agc Building on the namei() split which was introduced in 5.99.15 (see (5) 118 1.7 agc above), further changes will be introduced: see the changes to namei 119 1.7 agc outlined in Message-ID: <20080319053709.GB3951 (a] netbsd.org> for more 120 1.7 agc information. This will simplify the locking and behavior of namei() 121 1.7 agc calls within the kernel to resolve path names within file systems. 122 1.1 agc 123 1.1 agc Responsible: dholland 124 1.1 agc 125 1.1 agc 126 1.8 agc 10. Ephemeral Mapping 127 1.8 agc --------------------- 128 1.8 agc 129 1.8 agc Responsible: rmind 130 1.8 agc 131 1.8 agc 132 1.8 agc 11. Multicast DNS and DNS Service Discovery 133 1.8 agc ------------------------------------------- 134 1.8 agc 135 1.8 agc mDNSResponder (also known as mdnsd on some systems) is a daemon invoked 136 1.8 agc at boot time to implement Multicast DNS and DNS Service Discovery. On Mac 137 1.8 agc OS X 10.6 (Snow Leopard), mDNSResponder is also the system-wide Unicast 138 1.8 agc DNS Resolver. Ty Sarna added support for mdnsd to NetBSD-current, and it 139 1.8 agc will appear in NetBSD 6.0. 140 1.8 agc 141 1.1 agc 142 1.5 agc Alistair Crooks 143 1.8 agc Thu Nov 5 07:47:34 PST 2009 144
Indexes created Wed Sep 24 05:09:52 GMT 2025