and will bypass transfers for more than 8k. Blocks are invalidated after
2 seconds, so removable media should not confuse the cache.
The 8k threshold is a compromise; all UFS transfers performed by
libstand are 8k or less, so large file reads thrash the cache.
However many filesystem metadata operations are also performed using
8k blocks, so using a lower threshold gives poor performance.
Those of you with an eye for cache algorithms are welcome to tell me
how badly this one sucks; you can start with the 'bcachestats' command
which will print the contents of the cache and access statistics.
filesystems.
- New 'help' command and data in the help.* files (not yet installed),
provides topic and subtopic help, indexes, etc.
- Don't crash if the user tries to set an invalid console. Be helpful
instead.
- Expand tabs (badly) on the i386 video console.
- Some minor cosmetic changes.
Do a much better job of DWIM with partial device specifications.
Fix the module metadata build process, which was completely broken.
Use a larger read buffer when copying large objects in; this
improves performance marginally and will avoid flushning any small caches
we might choose to implement.
Strip any device name information from the kernel name
before passing it in.
biosdisk.c
Be more strict about matching device names to slice entries.
Only allow unsliced syntax on unsliced disks.
Allocate space for, and copy, NDOSPART slice entries from the
MBR, not just one. Add some extra debugging while we're at it.
elf_freebsd.c
Initialise the symbol table start/end pointers in case we don't
have them.
Use bd_getdev() to work out a dev_t for the root device.
Allow $rootdev to override $currdev as the root device.
biosdisk.c
Save the slice table and disklabel when opening a disk.
Add bd_getdev(), which attempts to return a dev_t corresponding
to a given device. Cases which it still doesn't get right:
- The inevitable da-when-wd-also-exists
- Disks with no slice table (the slice number is not set correctly)
The first is difficult to get right, the second will be
fixed in an upcoming commit.
comconsole.c
vidconsole.c
getchar() should return an 8-bit value; some BIOSsen pack extra
information in %eax.
libi386.h
Remove some stale prototypes, add new ones.
- Make the "what do we do with a drunken disklabel" if-then-else-regardless
tangle easier to read.
- Don't count on the v86 structure being preserved between loop iterations,
as it may be trampled eg. by the DEBUG call.
- Discard large amounts of BIOS-related code in favour of the more compact
BTX vm86 interface.
- Build the loader module as ELF, although the resulting object is a.out,
make gensetdefs 32/64-bit sensitive and use a single copy of it.
- Throw away installboot, as it's no longer required.
- Use direct bcopy operations in the i386_copy module, as BTX
maps the first 16M of memory. Check operations against the
detected size of actual memory.
'three-stage' bootstrap.
There are a number of caveats with the code in its current state:
- The i386 bootstrap only supports booting from a floppy.
- The kernel and kld do not yet know how to deal with the extended
information and module summary passed in.
- PnP-based autodetection and demand loading of modules is not implemented.
- i386 ELF kernel loading is not ready yet.
- The i386 bootstrap is loaded via an ugly blockmap.
On the alpha, both net- and disk-booting (SRM console machines only) is
supported. No blockmaps are used by this code.
Obtained from: Parts from the NetBSD/i386 standalone bootstrap.
