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163 Commits

Author SHA1 Message Date
Matthew Dillon
d2d00d11be NFS O_EXCL file create semantics temporarily uses file attributes to store
the file verifier.  The NFS client is supposed to do a SETATTR after a
successful O_EXCL open/create to clean up the attributes.  FreeBSD's
client code was generating a SETATTR rpc but was not generating an access
or modification time update within that rpc, leaving the file with a
broken access time that solaris chokes on (and it doesn't look very
nice when you ls -lua under FreeBSD either!).    Fixed.
2001-01-04 22:45:19 +00:00
Eivind Eklund
e3c4036b18 Give vop_mmap an untimely death. The opportunity to give it a timely
death timed out in 1996.
2000-11-01 17:57:24 +00:00
Boris Popov
c523a62949 Make nfs PDIRUNLOCK aware. Now it is possible to use nullfs mounts on top
of nfs mounts, but there can be side effects because nfs uses shared locks
for vnodes.
2000-10-15 08:06:32 +00:00
Boris Popov
823548e131 Add missed vop_stdunlock() for fifo's vnops (this affects only v2 mounts).
Give nfs's node lock its own name.
2000-10-15 08:01:28 +00:00
Boris Popov
67e871664b Add a lock structure to vnode structure. Previously it was either allocated
separately (nfs, cd9660 etc) or keept as a first element of structure
referenced by v_data pointer(ffs). Such organization leads to known problems
with stacked filesystems.

From this point vop_no*lock*() functions maintain only interlock lock.
vop_std*lock*() functions maintain built-in v_lock structure using lockmgr().
vop_sharedlock() is compatible with vop_stdunlock(), but maintains a shared
lock on vnode.

If filesystem wishes to export lockmgr compatible lock, it can put an address
of this lock to v_vnlock field. This indicates that the upper filesystem
can take advantage of it and use single lock structure for entire (or part)
of stack of vnodes. This field shouldn't be examined or modified by VFS code
except for initialization purposes.

Reviewed in general by:	mckusick
2000-09-25 15:24:04 +00:00
Poul-Henning Kamp
9626b608de Separate the struct bio related stuff out of <sys/buf.h> into
<sys/bio.h>.

<sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall
not be made a nested include according to bdes teachings on the
subject of nested includes.

Diskdrivers and similar stuff below specfs::strategy() should no
longer need to include <sys/buf.> unless they need caching of data.

Still a few bogus uses of struct buf to track down.

Repocopy by:    peter
2000-05-05 09:59:14 +00:00
Poul-Henning Kamp
2c9b67a8df Remove unneeded #include <vm/vm_zone.h>
Generated by:	src/tools/tools/kerninclude
2000-04-30 18:52:11 +00:00
Poul-Henning Kamp
87150cb06d s/biowait/bufwait/g
Prodded by: several.
2000-04-29 16:25:22 +00:00
Poul-Henning Kamp
3389ae9350 Remove ~25 unneeded #include <sys/conf.h>
Remove ~60 unneeded #include <sys/malloc.h>
2000-04-19 14:58:28 +00:00
Poul-Henning Kamp
8177437d85 Complete the bio/buf divorce for all code below devfs::strategy
Exceptions:
        Vinum untouched.  This means that it cannot be compiled.
        Greg Lehey is on the case.

        CCD not converted yet, casts to struct buf (still safe)

        atapi-cd casts to struct buf to examine B_PHYS
2000-04-15 05:54:02 +00:00
Poul-Henning Kamp
c244d2de43 Move B_ERROR flag to b_ioflags and call it BIO_ERROR.
(Much of this done by script)

Move B_ORDERED flag to b_ioflags and call it BIO_ORDERED.

Move b_pblkno and b_iodone_chain to struct bio while we transition, they
will be obsoleted once bio structs chain/stack.

Add bio_queue field for struct bio aware disksort.

Address a lot of stylistic issues brought up by bde.
2000-04-02 15:24:56 +00:00
Poul-Henning Kamp
b99c307a21 Rename the existing BUF_STRATEGY() to DEV_STRATEGY()
substitute BUF_WRITE(foo) for VOP_BWRITE(foo->b_vp, foo)

substitute BUF_STRATEGY(foo) for VOP_STRATEGY(foo->b_vp, foo)

This patch is machine generated except for the ccd.c and buf.h parts.
2000-03-20 11:29:10 +00:00
Poul-Henning Kamp
21144e3bf1 Remove B_READ, B_WRITE and B_FREEBUF and replace them with a new
field in struct buf: b_iocmd.  The b_iocmd is enforced to have
exactly one bit set.

B_WRITE was bogusly defined as zero giving rise to obvious coding
mistakes.

Also eliminate the redundant struct buf flag B_CALL, it can just
as efficiently be done by comparing b_iodone to NULL.

Should you get a panic or drop into the debugger, complaining about
"b_iocmd", don't continue.  It is likely to write on your disk
where it should have been reading.

This change is a step in the direction towards a stackable BIO capability.

A lot of this patch were machine generated (Thanks to style(9) compliance!)

Vinum users:  Greg has not had time to test this yet, be careful.
2000-03-20 10:44:49 +00:00
Matthew Dillon
54986abd15 Fix at least one source of the continued 'NFS append race'. close()
was calling nfs_flush() and then clearing the NMODIFIED bit.  This is
    not legal since there might still be dirty buffers after the nfs_flush
    (for example, pending commits).  The clearing of this bit in turn prevented
    a necessary vinvalbuf() from occuring leaving left over dirty buffers
    even after truncating the file in a new operation.  The fix is to
    simply not clear NMODIFIED.

    Also added a sysctl vfs.nfs.nfsv3_commit_on_close which, if set to 1,
    will cause close() to do a stage 1 write AND a stage 2 commit
    synchronously.  By default only the stage 1 write is done synchronously.

Reviewed by:	Alfred Perlstein <bright@wintelcom.net>
2000-01-05 00:32:18 +00:00
Eivind Eklund
762e6b856c Introduce NDFREE (and remove VOP_ABORTOP) 1999-12-15 23:02:35 +00:00
Matthew Dillon
ea94c7b968 Synopsis of problem being fixed: Dan Nelson originally reported that
blocks of zeros could wind up in a file written to over NFS by a client.
    The problem only occurs a few times per several gigabytes of data.   This
    problem turned out to be bug #3 below.

    bug #1:

        B_CLUSTEROK must be cleared when an NFS buffer is reverted from
        stage 2 (ready for commit rpc) to stage 1 (ready for write).
        Reversions can occur when a dirty NFS buffer is redirtied with new
        data.

        Otherwise the VFS/BIO system may end up thinking that a stage 1
        NFS buffer is clusterable.  Stage 1 NFS buffers are not clusterable.

    bug #2:

        B_CLUSTEROK was inappropriately set for a 'short' NFS buffer (short
        buffers only occur near the EOF of the file).  Change to only set
        when the buffer is a full biosize (usually 8K).  This bug has no
        effect but should be fixed in -current anyway.  It need not be
        backported.

    bug #3:

        B_NEEDCOMMIT was inappropriately set in nfs_flush() (which is
	typically only called by the update daemon).  nfs_flush()
        does a multi-pass loop but due to the lack of vnode locking it
        is possible for new buffers to be added to the dirtyblkhd list
        while a flush operation is going on.  This may result in nfs_flush()
        setting B_NEEDCOMMIT on a buffer which has *NOT* yet gone through its
        stage 1 write, causing only the commit rpc to be made and thus
        causing the contents of the buffer to be thrown away (never sent to
        the server).

    The patch also contains some cleanup, which only applies to the commit
    into -current.

Reviewed by:	dg, julian
Originally Reported by: Dan Nelson <dnelson@emsphone.com>
1999-12-12 06:09:57 +00:00
Matthew Dillon
98733bd871 The symlink implementation could improperly return a NULL vp along with
a 0 error code.  The problem occured with NFSv2 mounts and also with
    any NFSv3 mount returning an EEXIST error (which is translated to 0
    prior to return).  The reply to the rpc only contains the file handle
    for the no-error case under NFSv3.  The error case under NFSv3 and
    all cases under NFSv2 do *not* return the file handle.  The fix is
    to do a secondary lookup to obtain the file handle and thus be able
    to generate a return vnode for the situations where the rpc reply
    does not contain the required information.

    The bug was originally introduced when VOP_SYMLINK semantics were
    changed for -CURRENT.  The NFS symlink implementation was not properly
    modified to go along with the change despite the fact that three
    people reviewed the code.  It took four attempts to get the current
    fix correct with five people.  Is NFS obfuscated?  Ha!

Reviewed by:	Alfred Perlstein <bright@wintelcom.net>
Testing and Discussion: "Viren R.Shah" <viren@rstcorp.com>, Eivind Eklund <eivind@FreeBSD.ORG>, Ian Dowse <iedowse@maths.tcd.ie>
1999-11-30 06:56:15 +00:00
Eivind Eklund
679106b15a Remap the error EEXISTS => 0 *before* using error to determine if we should
return a vp.
1999-11-27 18:14:41 +00:00
Eivind Eklund
b6335212d6 Fix VOP_MKNOD for loss of WILLRELE. I don't know how I could have missed
this in the first place :-(

Noticed by:	bde
1999-11-20 16:09:10 +00:00
Eivind Eklund
dd8c04f4c7 Remove WILLRELE from VOP_SYMLINK
Note: Previous commit to these files (except coda_vnops and devfs_vnops)
that claimed to remove WILLRELE from VOP_RENAME actually removed it from
VOP_MKNOD.
1999-11-13 20:58:17 +00:00
Matthew Dillon
a5d3fe3f85 Move NFS access cache hits/misses into nfsstats structure so
/usr/bin/nfsstat can get to it easily.
1999-10-25 19:22:33 +00:00
Poul-Henning Kamp
3b6fb88590 Before we start to mess with the VFS name-cache clean things up a little bit:
Isolate the namecache in its own file, and give it a dedicated malloc type.
1999-10-03 12:18:29 +00:00
Matthew Dillon
b5acbc8b9c Asynchronized client-side nfs_commit. NFS commit operations were
previously issued synchronously even if async daemons (nfsiod's) were
    available.  The commit has been moved from the strategy code to the doio
    code in order to asynchronize it.

    Removed use of lastr in preparation for removal of vnode->v_lastr.  It
    has been replaced with seqcount, which is already supported by the system
    and, in fact, gives us a better heuristic for sequential detection then
    lastr ever did.

    Made major performance improvements to the server side commit.  The
    server previously fsync'd the entire file for each commit rpc.  The
    server now bawrite()s only those buffers related to the offset/size
    specified in the commit rpc.

    Note that we do not commit the meta-data yet.  This works still needs
    to be done.

    Note that a further optimization can be done (and has not yet been done)
    on the client: we can merge multiple potential commit rpc's into a
    single rpc with a greater file offset/size range and greatly reduce
    rpc traffic.

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:57:57 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Poul-Henning Kamp
0ef1c82630 Decommision miscfs/specfs/specdev.h. Most of it goes into <sys/conf.h>,
a few lines into <sys/vnode.h>.

Add a few fields to struct specinfo, paving the way for the fun part.
1999-08-08 18:43:05 +00:00
Mike Smith
98f8aa275b As described by the submitter:
I did some tcpdumping the other day and noticed that GETATTR calls
  were frequently followed by an ACCESS call to the same file. The
  attached patch changes nfs_getattr to fill the access cache as a side
  effect. This is accomplished by calling ACCESS rather than
  GETATTR. This implies a modest overhead of 4 bytes in the request and
  8 bytes in the response compared to doing a vanilla GETATTR.
...
  [The patch comprises two parts] The first
  is the "real" patch, the second counts misses and hits rather than
  fills and hits. The difference is subtle but important because both
  nfs_getattr and nfs_access now fill the cache. It also changes the
  default value of nfsaccess_cache_timeout to better match the attribute
  cache. IMHO, file timestamps change much more frequently than
  protection bits.

Submitted by:	Bjoern Groenvall <bg@sics.se>
Reviewed by:	dillon (partially)
1999-07-31 01:51:58 +00:00
Bill Paul
44fe63e5e7 Close PR #12651: the hash calculation routine has changed in other
parts of the kernel but was not updated in nfs_readdirplusrpc().
1999-07-30 04:51:35 +00:00
Bill Paul
f069164876 Fix two bugs in nfs_readdirplus(). The first is that in some cases,
vnodes are locked and never unlocked, which leads to processes starting
to wedge up after doing a mount -o nfsv3,tcp,rdirplus foo:/fs /fs; ls /fs.
The second is that sometimes cnp is accessed without having been
properly initialized: cnp->cn_nameptr points to an earlier name while
"len" contains the length of a current name of different size. This
leads to an attempt to dereference *(cn->cn_nameptr + len) which will
sometimes cause a page fault and a panic.

With these two fixes, client side readdirplus works correctly with
FreeBSD, IRIX 6.5.4 and Solaris 2.5.1 and 2.6 servers.

Submitted by: Matthew Dillon <dillon@backplane.com>
1999-07-30 04:02:04 +00:00
Peter Wemm
8180de4a33 Fix warning. va_fsid is udev_t, which is int32_t. No need to use %lx. 1999-07-01 13:32:54 +00:00
Julian Elischer
c1f020038b Submitted by: Conrad Minshall <conrad@apple.com>
Reviewed by: Matthew Dillon <dillon@apollo.backplane.com>

The following ugly hack to the exit path of nfs_readlinkrpc() circumvents
an Auspex bug: for symlinks longer than 112 (0x70) they return a 1024 byte
xdr string - the correct data with many nulls appended.  Without this fix
namei returns ENAMETOOLONG, at least it does on our source base and on
FreeBSD 3.0.  Note we do not (and should not) rely upon their null padding.
1999-06-30 02:53:51 +00:00
Peter Wemm
5fc491ef58 Fix a KASSERT() that was negated and lead to:
nfs_strategy: buffer 0xxxxx not locked
when you attempted to write and had INVARIANTS turned on.
1999-06-28 12:34:40 +00:00
Kirk McKusick
67812eacd7 Convert buffer locking from using the B_BUSY and B_WANTED flags to using
lockmgr locks. This commit should be functionally equivalent to the old
semantics. That is, all buffer locking is done with LK_EXCLUSIVE
requests. Changes to take advantage of LK_SHARED and LK_RECURSIVE will
be done in future commits.
1999-06-26 02:47:16 +00:00
Kirk McKusick
f9c8cab591 Add a vnode argument to VOP_BWRITE to get rid of the last vnode
operator special case. Delete special case code from vnode_if.sh,
vnode_if.src, umap_vnops.c, and null_vnops.c.
1999-06-16 23:27:55 +00:00
Peter Wemm
b903b04cc0 Various changes lifted from the OpenBSD cvs tree:
txdr_hyper and fxdr_hyper tweaks to avoid excessive CPU order knowledge.

nfs_serv.c: don't call nfsm_adj() with negative values, windows clients
could crash servers when doing a readdir of a large directory.

nfs_socket.c: Use IP_PORTRANGE to get a priviliged port without a spin
loop trying to bind().  Don't clobber a mbuf pointer or we get panics
on a NFS3ERR_JUKEBOX error from a server when reusing a freed mbuf.

nfs_subs.c: Don't loose st_blocks on NFSv2 mounts when > 2GB.

Obtained from:  OpenBSD
1999-06-05 05:35:03 +00:00
Poul-Henning Kamp
bfbb9ce670 Divorce "dev_t" from the "major|minor" bitmap, which is now called
udev_t in the kernel but still called dev_t in userland.

Provide functions to manipulate both types:
        major()         umajor()
        minor()         uminor()
        makedev()       umakedev()
        dev2udev()      udev2dev()

For now they're functions, they will become in-line functions
after one of the next two steps in this process.

Return major/minor/makedev to macro-hood for userland.

Register a name in cdevsw[] for the "filedescriptor" driver.

In the kernel the udev_t appears in places where we have the
major/minor number combination, (ie: a potential device: we
may not have the driver nor the device), like in inodes, vattr,
cdevsw registration and so on, whereas the dev_t appears where
we carry around a reference to a actual device.

In the future the cdevsw and the aliased-from vnode will be hung
directly from the dev_t, along with up to two softc pointers for
the device driver and a few houskeeping bits.  This will essentially
replace the current "alias" check code (same buck, bigger bang).

A little stunt has been provided to try to catch places where the
wrong type is being used (dev_t vs udev_t), if you see something
not working, #undef DEVT_FASCIST in kern/kern_conf.c and see if
it makes a difference.  If it does, please try to track it down
(many hands make light work) or at least try to reproduce it
as simply as possible, and describe how to do that.

Without DEVT_FASCIST I belive this patch is a no-op.

Stylistic/posixoid comments about the userland view of the <sys/*.h>
files welcome now, from userland they now contain the end result.

Next planned step: make all dev_t's refer to the same devsw[] which
means convert BLK's to CHR's at the perimeter of the vnodes and
other places where they enter the game (bootdev, mknod, sysctl).
1999-05-11 19:55:07 +00:00
Poul-Henning Kamp
b0eeea2042 remove b_proc from struct buf, it's (now) unused.
Reviewed by:	dillon, bde
1999-05-06 20:00:34 +00:00
Peter Wemm
dfd5dee1b0 Add sufficient braces to keep egcs happy about potentially ambiguous
if/else nesting.
1999-05-06 18:13:11 +00:00
Alan Cox
7f2f2dae43 All directory accesses must be made with NFS_DIRBLKSIZE chunks to avoid
confusing the directory read cookie cache.  The nfs_access implementation
for v2 mounts attempts to read from the directory if root is the user
so that root can't access cached files when the server remaps root
to some other user.

Submitted by:	Doug Rabson <dfr@nlsystems.com>
Reviewed by:	Matthew Dillon <dillon@apollo.backplane.com>
1999-05-03 20:59:14 +00:00
Alan Cox
4221e284a3 The VFS/BIO subsystem contained a number of hacks in order to optimize
piecemeal, middle-of-file writes for NFS.  These hacks have caused no
end of trouble, especially when combined with mmap().  I've removed
them.  Instead, NFS will issue a read-before-write to fully
instantiate the struct buf containing the write.  NFS does, however,
optimize piecemeal appends to files.  For most common file operations,
you will not notice the difference.  The sole remaining fragment in
the VFS/BIO system is b_dirtyoff/end, which NFS uses to avoid cache
coherency issues with read-merge-write style operations.  NFS also
optimizes the write-covers-entire-buffer case by avoiding the
read-before-write.  There is quite a bit of room for further
optimization in these areas.

The VM system marks pages fully-valid (AKA vm_page_t->valid =
VM_PAGE_BITS_ALL) in several places, most noteably in vm_fault.  This
is not correct operation.  The vm_pager_get_pages() code is now
responsible for marking VM pages all-valid.  A number of VM helper
routines have been added to aid in zeroing-out the invalid portions of
a VM page prior to the page being marked all-valid.  This operation is
necessary to properly support mmap().  The zeroing occurs most often
when dealing with file-EOF situations.  Several bugs have been fixed
in the NFS subsystem, including bits handling file and directory EOF
situations and buf->b_flags consistancy issues relating to clearing
B_ERROR & B_INVAL, and handling B_DONE.

getblk() and allocbuf() have been rewritten.  B_CACHE operation is now
formally defined in comments and more straightforward in
implementation.  B_CACHE for VMIO buffers is based on the validity of
the backing store.  B_CACHE for non-VMIO buffers is based simply on
whether the buffer is B_INVAL or not (B_CACHE set if B_INVAL clear,
and vise-versa).  biodone() is now responsible for setting B_CACHE
when a successful read completes.  B_CACHE is also set when a bdwrite()
is initiated and when a bwrite() is initiated.  VFS VOP_BWRITE
routines (there are only two - nfs_bwrite() and bwrite()) are now
expected to set B_CACHE.  This means that bowrite() and bawrite() also
set B_CACHE indirectly.

There are a number of places in the code which were previously using
buf->b_bufsize (which is DEV_BSIZE aligned) when they should have
been using buf->b_bcount.  These have been fixed.  getblk() now clears
B_DONE on return because the rest of the system is so bad about
dealing with B_DONE.

Major fixes to NFS/TCP have been made.  A server-side bug could cause
requests to be lost by the server due to nfs_realign() overwriting
other rpc's in the same TCP mbuf chain.  The server's kernel must be
recompiled to get the benefit of the fixes.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
1999-05-02 23:57:16 +00:00
Julian Elischer
4ef2094e45 Reviewed by: Many at differnt times in differnt parts,
including alan, john, me, luoqi, and kirk
Submitted by:	Matt Dillon <dillon@frebsd.org>

This change implements a relatively sophisticated fix to getnewbuf().
There were two problems with getnewbuf(). First, the writerecursion
can lead to a system stack overflow when you have NFS and/or VN
devices in the system. Second, the free/dirty buffer accounting was
completely broken. Not only did the nfs routines blow it trying to
manually account for the buffer state, but the accounting that was
done did not work well with the purpose of their existance: figuring
out when getnewbuf() needs to sleep.

The meat of the change is to kern/vfs_bio.c. The remaining diffs are
all minor except for NFS, which includes both the fixes for bp
interaction AND fixes for a 'biodone(): buffer already done' lockup.
Sys/buf.h also contains a chaining structure which is not used by
this patchset but is used by other patches that are coming soon.
This patch deliniated by tags PRE_MAT_GETBUF and POST_MAT_GETBUF.
(sorry for the missing T matt)
1999-03-12 02:24:58 +00:00
Doug Rabson
ce02431ffa * Change sysctl from using linker_set to construct its tree using SLISTs.
This makes it possible to change the sysctl tree at runtime.

* Change KLD to find and register any sysctl nodes contained in the loaded
  file and to unregister them when the file is unloaded.

Reviewed by: Archie Cobbs <archie@whistle.com>,
	Peter Wemm <peter@netplex.com.au> (well they looked at it anyway)
1999-02-16 10:49:55 +00:00
Matthew Dillon
2a2ecc3027 General additional cleanup of VOP API for NFS ops - mainly NFS ignoring
the API for freeing up cnp's.  This cleanup should not effect nominal
    operation one way or the other since NFS VOPs just happen to be called
    with flags that match what it actually does to the NAMEI components it
    gets.  Still, if an NFS error occured, there was probably some memory
    leakage of NAMEI components with certain NFS VOP ops.
1999-02-13 09:47:30 +00:00
Matthew Dillon
5e9d4f1303 PR: kern/9970
Remove incorrect vput() in nfs_link()
1999-02-13 08:01:59 +00:00
Matthew Dillon
61da17a62c Flush delayed-write data out prior to issuing a rename rpc. This appears
to fix the problem w/ NFSV3 whereby a make installworld would get into
    high-network-bandwidth situations continuously trying to retry nfs writes
    that fail with a 'stale file handle' error.
1999-02-06 07:48:56 +00:00
Matthew Dillon
cdb96ab470 Fix nasty bug in nfs_access(). A conditional was if (a = b) instead of
if (a == b).
1999-01-27 22:45:49 +00:00
Matthew Dillon
53b3bd0e25 Fix warnings in preparation for adding -Wall -Wcast-qual to the
kernel compile
1999-01-27 22:45:13 +00:00
Matthew Dillon
1c7c3c6a86 This is a rather large commit that encompasses the new swapper,
changes to the VM system to support the new swapper, VM bug
    fixes, several VM optimizations, and some additional revamping of the
    VM code.  The specific bug fixes will be documented with additional
    forced commits.  This commit is somewhat rough in regards to code
    cleanup issues.

Reviewed by:	"John S. Dyson" <root@dyson.iquest.net>, "David Greenman" <dg@root.com>
1999-01-21 08:29:12 +00:00
Eivind Eklund
f65b39828c Remove two cases of unused variable sp3. 1999-01-12 12:39:14 +00:00
Doug Rabson
6cd60632a6 Fix for creating files on a Solaris 7 server with NFSv3 (the request was
slightly garbled but older servers seemed to understand it).

Reviewed by: David O'Brien <obrien@nuxi.ucdavis.edu>
1998-12-25 10:34:27 +00:00
Mike Smith
ad6d02135b Reimplement the NFS ACCESS RPC cache as an "accelerator" rather than a true
cache.  If the cached result lets us say "yes", then go with that.  If
we're not sure, or we think the answer might be "no", go to the wire to be
certain.    This avoids all of the possible false veto cases, and allows us
to key the cached value with just the UID for which the cached value holds,
reducing the bloat of the nfsnode structure from 104 bytes to just 12 bytes.

Since the "yes" case is by far the most common, this should still provide
a substantial performance improvement.  Also default the cache to on, with
a conservative timeout (2 seconds).  This improves performance if NFS is
loaded as a KLD module, as there's not (yet) code to parse an option out
of the module arguments to set it, and sysctl doesn't work (yet) for OIDs
in modules.

The 'accelerator' mode was suggested by Bjoern Groenvall (bg@sics.se)

Feedback on this would be appreciated as testing has been necessarily
limited by Comdex, and it would be valuable to have this in 2.2.8.
1998-11-15 20:36:18 +00:00