i386/79779: If system memory is above 4GB, one parts of memory will be ignored.

Thu Apr 14 23:50:27 PDT 2005

The following reply was made to PR i386/79779; it has been noted by GNATS.

From: =?big5?B?ZXJpYy5jaG8gKKj0rbOnuyk=?= <eric.cho at gigabyte.com.tw>
To: "Marc Olzheim" <marcolz at stack.nl>,
	<freebsd-gnats-submit at freebsd.org>
Cc: =?big5?B?ZXJpYy5jaG8gKKj0rbOnuyk=?= <eric.cho at gigabyte.com.tw>
Subject: RE: i386/79779: If system memory is above 4GB, one parts of memory    will be ignored.
Date: Fri, 15 Apr 2005 14:44:57 +0800

 Hi Marc:

 Sorry for late reply.
 Our update is below for your reference.
 1. After we update the kernel to 5.4, the issue still exists.
 Kernel information:
 FreeBSD db2 5.4-STABLE FreeBSD 5.4-STABLE #0: Wed Apr  6 03:28:10 CST =
 2005 root at db2:/usr/obj/usr/src/sys/BSD53  i386

 real memory  =3D 3220045824 (3070 MB)
 avail memory =3D 3153928192 (3007 MB)

 2. My platform is Lindenhurst (7520) + ICH5 and I can reproduce the same =
 issue on other platforms.
 Ex:=20
 Other Intel chipset (7501)
 FreeBSD www2 5.4-STABLE FreeBSD 5.4-STABLE #0: Wed Apr  6 03:28:10 CST =
 2005 root at www2:/usr/obj/usr/src/sys/BSD53  i386

 real memory  =3D 4026466304 (3839 MB)
 avail memory =3D 3946156032 (3763 MB)

 AMD platform:
 FreeBSD 5.4-STABLE #0: Wed Apr  6 03:28:10 CST 2005
     root at db7:/usr/obj/usr/src/sys/BSD53

 real memory  =3D 4227268608 (4031 MB)
 avail memory =3D 4143411200 (3951 MB)

 3. These three platforms all have 4GB (4096), but any of real memory is =
 smaller than 4GB. We get one conclusion that the real memory size is =
 decided by PCI resource base.
 In my example, its PCI resource will locate 0C0000000h ~ 0FFFFFFFFh, the =
 range of memory address will be reserved for PCI, so the real avail =
 memory under 4GB is only 000000000h ~ 0C0000000h about 3GB. Other memory =
 (about 1GB) will re-map to over 4GB address. Other platforms are also =
 due to this reason.

 4. So, the issue seems the current FreeBSD cannot use over 4GB memory, =
 right?

 Please kindly suggest.
 Thanks.

 Best Regards, Eric

 -----Original Message-----
 From: Marc Olzheim [mailto:marcolz at stack.nl]=20
 Sent: Monday, April 11, 2005 7:17 PM
 To: freebsd-gnats-submit at FreeBSD.org; eric.cho (=A8=F4=AD=B3=A7=BB)
 Cc: marcolz at stack.nl
 Subject: Re: i386/79779: If system memory is above 4GB, one parts of =
 memory will be ignored.

 Could you please try this on a less ancient release, like >=3D 5.3 ?

 Marc