diff options
| author | dyson <dyson@FreeBSD.org> | 1997-06-15 17:56:53 +0000 |
|---|---|---|
| committer | dyson <dyson@FreeBSD.org> | 1997-06-15 17:56:53 +0000 |
| commit | eb8e1f5e4ef9200ddb9a6b5da00a52e14013f8f8 (patch) | |
| tree | eeee2fc9d75d47696a1cced34c51c39d48b94baa /sys/sys/buf.h | |
| parent | d85a7bf572a5808b870fb2878eb9b8674bb321e2 (diff) | |
| download | FreeBSD-src-eb8e1f5e4ef9200ddb9a6b5da00a52e14013f8f8.zip FreeBSD-src-eb8e1f5e4ef9200ddb9a6b5da00a52e14013f8f8.tar.gz | |
Fix a problem with the VN device. Specifically, the VN device can
cause a problem of spiraling death due to buffer resource limitations.
The vfs_bio code in general had little ability to handle buffer resource
management, and now it does. Also, there are a lot more knobs for tuning the
vfs_bio code now. The knobs came free because of the need that there
always be some immediately available buffers (non-delayed or locked) for
use. Note that the buffer cache code is much less likely to get bogged
down with lots of delayed writes, even more so than before.
Diffstat (limited to 'sys/sys/buf.h')
| -rw-r--r-- | sys/sys/buf.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/sys/sys/buf.h b/sys/sys/buf.h index e52c809..8cb3c8c 100644 --- a/sys/sys/buf.h +++ b/sys/sys/buf.h @@ -36,7 +36,7 @@ * SUCH DAMAGE. * * @(#)buf.h 8.9 (Berkeley) 3/30/95 - * $Id$ + * $Id: buf.h,v 1.38 1997/02/22 09:44:49 peter Exp $ */ #ifndef _SYS_BUF_H_ @@ -194,6 +194,7 @@ extern char *buffers; /* The buffer contents. */ extern int bufpages; /* Number of memory pages in the buffer pool. */ extern struct buf *swbuf; /* Swap I/O buffer headers. */ extern int nswbuf; /* Number of swap I/O buffer headers. */ +extern int needsbuffer, numdirtybuffers; extern TAILQ_HEAD(swqueue, buf) bswlist; void bufinit __P((void)); @@ -244,6 +245,7 @@ void vm_bounce_alloc __P((struct buf *)); void vm_bounce_free __P((struct buf *)); vm_offset_t vm_bounce_kva_alloc __P((int)); void vm_bounce_kva_alloc_free __P((vm_offset_t, int)); +void vfs_bio_need_satisfy __P((void)); #endif /* KERNEL */ #endif /* !_SYS_BUF_H_ */ |
