system revision 1.9
1 1.9 agc $NetBSD: system,v 1.9 2012/01/15 02:49:12 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 1.9 agc The following projects will appear in NetBSD 6.0: 10 1.6 agc 1. 64-bit time values supported 11 1.6 agc 2. Better Kernel Modules support 12 1.8 agc 5. namei() tactical changes 13 1.9 agc 9. namei() strategic changes 14 1.8 agc 10. emap (ephemeral mapping) support for i386 and amd64 15 1.8 agc 11. support for mDNSResponder 16 1.8 agc 17 1.9 agc The following projects may make it into future releases: 18 1.6 agc 3. Full kernel preemption for real-time threads 19 1.6 agc 4. POSIX shared memory 20 1.6 agc 6. Better resource controls 21 1.6 agc 7. Improved observability: online crashdumps, remote debugging 22 1.6 agc 8. Processor and cache topology aware scheduler 23 1.1 agc 24 1.1 agc We'll continue to update this roadmap as features and dates get firmed up. 25 1.1 agc 26 1.1 agc 27 1.1 agc Some explanations 28 1.1 agc ================= 29 1.1 agc 30 1.6 agc 1. 64-bit time_t support 31 1.1 agc ------------------------- 32 1.1 agc 33 1.1 agc The Unix 32-bit time_t value will overflow in 2037 - any mortgage calculations 34 1.1 agc which use a time_t value are in danger of overflowing at the present time - 35 1.1 agc and to address this, 64-bit time_t values will be used to contain the number 36 1.7 agc of seconds since 1970. This was completed in 5.99.7 by Christos (with no libc 37 1.7 agc major bump - kudos and respect), and will be in 6.0. 38 1.1 agc 39 1.1 agc Responsible: christos 40 1.1 agc 41 1.6 agc 2. Better Kernel Module Support 42 1.6 agc ------------------------------- 43 1.6 agc 44 1.6 agc Starting with 5.99.2, the kernel support for modules was enhanced by 45 1.6 agc ad, and GENERIC was switched over to be a MODULAR kernel. Support 46 1.6 agc from booting from modules, like ffs, was introduced at the same time. 47 1.6 agc Some work has been done by Luke Mewburn in this area to define module 48 1.6 agc locations and paths so that effective kernel development can be done 49 1.8 agc using modules. Kernel modules have been moved out of base.tgz and a new 50 1.8 agc modules.tgz has been created. 51 1.6 agc 52 1.6 agc Responsible: ad, lukem 53 1.6 agc 54 1.7 agc 3. Full kernel preemption for real-time threads on non-x86 55 1.7 agc ---------------------------------------------------------- 56 1.5 agc 57 1.7 agc With the revamp of the kernel concurrency model, much of the kernel is 58 1.7 agc fully multi-threaded and can therefore be preempted at any time. In 59 1.7 agc support of lower context switch and dispatch times for real-time 60 1.7 agc threads, full kernel preemption is being implemented. This has been 61 1.7 agc implemented already for i386 and x86_64 (and is in 5.0), but needs to 62 1.7 agc be extended to support the ARM, MIPS and SuperH ports. 63 1.7 agc 64 1.7 agc Responsible: rmind 65 1.5 agc 66 1.9 agc 67 1.6 agc 4. POSIX shared memory 68 1.6 agc ---------------------- 69 1.1 agc 70 1.1 agc Implement POSIX shared memory facilities, which can be used to create the 71 1.1 agc shared memory objects and add the memory locations to the address space of 72 1.1 agc a process. 73 1.1 agc 74 1.1 agc Responsible: rmind 75 1.1 agc 76 1.9 agc 77 1.6 agc 5. Incremental namei improvements, Phase 1 78 1.6 agc ------------------------------------------ 79 1.1 agc 80 1.6 agc In NetBSD 5.99.15, some changes were made to split the namei() routine 81 1.6 agc up into logical parts, so that changes can be made to the constituent 82 1.7 agc parts in a less intrusive way. This is in the repository now, and will 83 1.7 agc be in 6.0. 84 1.1 agc 85 1.1 agc Responsible: dholland 86 1.1 agc 87 1.9 agc 88 1.6 agc 6. Better resource controls 89 1.6 agc --------------------------- 90 1.1 agc 91 1.1 agc A resource provisioning and control framework that extends beyond the 92 1.1 agc traditional Unix process limits. 93 1.1 agc 94 1.9 agc Responsible: TBD 95 1.9 agc 96 1.9 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 1.9 agc Responsible: TBD 104 1.9 agc 105 1.9 agc 106 1.6 agc 8. Processor and cache topology aware scheduler 107 1.6 agc ----------------------------------------------- 108 1.1 agc 109 1.1 agc Implement the detection of the topology of the processors and caches. 110 1.1 agc Improve the scheduler to make decisions about thread migration 111 1.1 agc according to the topology, to get better thread affinity and less 112 1.1 agc cache thrashing, and thus improve overall performance in modern SMP 113 1.1 agc systems. 114 1.1 agc 115 1.1 agc Responsible: rmind 116 1.1 agc 117 1.9 agc 118 1.6 agc 9. Incremental namei improvements, Phase 2 119 1.6 agc ------------------------------------------ 120 1.1 agc 121 1.7 agc Building on the namei() split which was introduced in 5.99.15 (see (5) 122 1.7 agc above), further changes will be introduced: see the changes to namei 123 1.7 agc outlined in Message-ID: <20080319053709.GB3951 (a] netbsd.org> for more 124 1.7 agc information. This will simplify the locking and behavior of namei() 125 1.7 agc calls within the kernel to resolve path names within file systems. 126 1.1 agc 127 1.1 agc Responsible: dholland 128 1.1 agc 129 1.1 agc 130 1.8 agc 10. Ephemeral Mapping 131 1.8 agc --------------------- 132 1.8 agc 133 1.8 agc Responsible: rmind 134 1.8 agc 135 1.8 agc 136 1.8 agc 11. Multicast DNS and DNS Service Discovery 137 1.8 agc ------------------------------------------- 138 1.8 agc 139 1.8 agc mDNSResponder (also known as mdnsd on some systems) is a daemon invoked 140 1.8 agc at boot time to implement Multicast DNS and DNS Service Discovery. On Mac 141 1.8 agc OS X 10.6 (Snow Leopard), mDNSResponder is also the system-wide Unicast 142 1.8 agc DNS Resolver. Ty Sarna added support for mdnsd to NetBSD-current, and it 143 1.8 agc will appear in NetBSD 6.0. 144 1.8 agc 145 1.1 agc 146 1.5 agc Alistair Crooks 147 1.9 agc Sat Jan 14 11:40:49 PST 2012 148
Indexes created Tue Sep 23 23:09:58 GMT 2025