diff options
| author | Poul-Henning Kamp <phk@FreeBSD.org> | 1996-11-16 21:34:19 +0000 |
|---|---|---|
| committer | Poul-Henning Kamp <phk@FreeBSD.org> | 1996-11-16 21:34:19 +0000 |
| commit | c49818001ac974e42db52cda3417d137a3455c1e (patch) | |
| tree | 2ccd8fe66e3d6861325dfe5946c33e5a35878ee9 /lib/libc/sys | |
| parent | 42ff3e9e3a49d7a52285358558894d6c2d14f466 (diff) | |
Notes
Diffstat (limited to 'lib/libc/sys')
| -rw-r--r-- | lib/libc/sys/mmap.2 | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/lib/libc/sys/mmap.2 b/lib/libc/sys/mmap.2 index d70d871ac54b..32fcb44075b9 100644 --- a/lib/libc/sys/mmap.2 +++ b/lib/libc/sys/mmap.2 @@ -213,13 +213,13 @@ was specified and insufficient memory was available. .Sh BUGS .Ar len -is limit to 2GB. Mmapping slightly more than 2GB doesn't work, but -mapping a window of size (filesize % 2GB) for file sizes of slightly -less than 2G, 4GB, 6GB and 8GB. +is limited to 2GB. Mmapping slightly more than 2GB doesn't work, but +it is possible to map a window of size (filesize % 2GB) for file sizes +of slightly less than 2G, 4GB, 6GB and 8GB. The limit is imposed for a variety of reasons. Most of them have to do with FreeBSD not wanting to use 64 bit offsets in the VM system due to -the extreme performance penalty. So FreeBSD use 32bit page indexes and +the extreme performance penalty. So FreeBSD uses 32bit page indexes and this gives FreeBSD a maximum of 8TB filesizes. It's actually bugs in the filesystem code that causes the limit to be further restricted to 1TB (loss of precision when doing blockno calculations). |
