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tsoome 6e818b85ef loader: bcache read ahead block count should take account the large sectors
The loader bcache is implementing simple read-ahead to boost the cache.
The bcache is built based on 512B block sizes, and the read ahead is attempting
to read number of cache blocks, based on amount of the free bcache space.

However, there are devices using larger sector sizes than 512B, most obviously
the CD media is based on 2k sectors. This means the read-ahead can not be just
random number of blocks, but we should use value suitable also for use with
larger sectors, as for example, with CD devices, we should read multiple of 2KB.
Since the sector size from disk interface is not too reliable, i guess we can
just use "good enough" value, so the implementation is rounding down the read
ahead block count to be multiple of 16.

This means we have covered sector sizes to 8k.

In addition, the update does implement the end of cache marker, to help to
detect the possible memory corruption - I have not seen it happening so far,
but it does not hurt to have the detection mechanism in place.

Reviewed by:	allanjude
Approved by:	allanjude (mentor)
Differential Revision:	https://reviews.freebsd.org/D9179
2017-02-06 08:58:40 +00:00
bin Remove bdes(1) 2017-02-06 08:27:19 +00:00
cddl Search for _DTRACE_VERSION in sys/sdt.h rather than unistd.h. 2017-02-05 02:45:35 +00:00
contrib Merge projects/ipsec into head/. 2017-02-06 08:49:57 +00:00
crypto Merge OpenSSL 1.0.2k. 2017-01-26 19:10:29 +00:00
etc Use kldload -n when loading if_deqna 2017-02-05 08:24:37 +00:00
gnu Bump GCC FBSD_CC_VER for r312899 (-march=octeon+ support) 2017-02-01 05:24:17 +00:00
include Make use of clang nullability attributes. 2017-01-28 20:54:43 +00:00
kerberos5 Conditionalize adding ${KRB5DIR}/lib/gssapi/krb5/gkrb5_err.et to ETSRCS 2017-01-02 19:03:01 +00:00
lib Merge projects/ipsec into head/. 2017-02-06 08:49:57 +00:00
libexec Try to fix the old "he capability is stupid" bug in gettytab(5)/getty(8) 2017-02-02 20:30:50 +00:00
release Add some comments with examples on how to build Vagrant images. 2017-02-01 16:15:23 +00:00
rescue Remove pc98 support completely. 2017-01-28 02:22:15 +00:00
sbin Merge projects/ipsec into head/. 2017-02-06 08:49:57 +00:00
secure Remove bdes(1) 2017-02-06 08:27:19 +00:00
share Merge projects/ipsec into head/. 2017-02-06 08:49:57 +00:00
sys loader: bcache read ahead block count should take account the large sectors 2017-02-06 08:58:40 +00:00
targets Remove pc98 support completely. 2017-01-28 02:22:15 +00:00
tests Replace for/retry loops with "wait_for_ggate_device" calls and check 2017-02-02 03:54:43 +00:00
tools o Add mkimg to the cross tools, and use the TMPPATH as PATH to pick up 2017-02-06 06:15:38 +00:00
usr.bin Merge projects/ipsec into head/. 2017-02-06 08:49:57 +00:00
usr.sbin Replace Cyrillic characters with Latin (normal) ones. 2017-02-03 16:21:30 +00:00
.arcconfig callsign isn't required anymore 2016-09-29 06:19:45 +00:00
.arclint phabricator related changes: 2015-04-20 20:33:22 +00:00
COPYRIGHT Bump copyright year. 2016-12-31 12:41:42 +00:00
LOCKS
MAINTAINERS Remove myself from kern_timeout.c yeah! 2016-07-27 20:37:32 +00:00
Makefile Remove pc98 support completely. 2017-01-28 02:22:15 +00:00
Makefile.inc1 Remove LOCAL_LIB_DIRS warning added in r275839. 2017-02-04 02:15:49 +00:00
Makefile.libcompat Use cross-NM (XNM) in compat32 build 2017-01-27 03:43:18 +00:00
ObsoleteFiles.inc Add removed headers into the ObsoleteFiles.inc. 2017-02-06 08:56:04 +00:00
README README: remove nonexistent 'games' directory. 2016-05-18 10:43:13 +00:00
UPDATING Rename LLD_AS_LD to LLD_IS_LD, for consistency with CLANG_IS_CC 2017-01-27 01:59:12 +00:00

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