Ed Maste 01715d8cd1 speed up ar(1) on UFS file systems ... Fault in the buffer prior to writing to workaround poor performance due to interaction with kernel fs deadlock avoidance code. See the comment prior to vn_io_fault_doio() in sys/kern/vfs_vnops.c for details of the issue. On my stable/10 desktop with a 16MB obj.o and "ar r out.a obj.o" I see the following run times (seconds): x ar.r284891 + ar.patched +----------------------------------------------------------------------+ |+ | |+ x| |+ xx| |A |A| +----------------------------------------------------------------------+ N Min Max Median Avg Stddev x 3 1.307 1.321 1.315 1.3143333 0.0070237692 + 3 0.020 0.023 0.022 0.021666667 0.0015275252 Difference at 95.0% confidence -1.29267 +/- 0.0115203 -98.3515% +/- 0.876513% (Student's t, pooled s = 0.00508265) Thanks to kib for diagnosing and explaining the issue and suggesting the workaround. Reviewed by: eadler, kib MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D2933		2015-06-29 13:48:44 +00:00
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acplex.l
acpyacc.y
ar.1	use .Mt to mark up email addresses consistently (part3)	2014-06-23 08:23:05 +00:00
ar.c
ar.h
Makefile	Convert to usr.bin/ to LIBADD	2014-11-25 14:29:10 +00:00
Makefile.depend	new depends	2015-06-16 23:37:19 +00:00
read.c	Avoid escaping EOL for line continuation	2015-04-09 15:08:39 +00:00
util.c
write.c	speed up ar(1) on UFS file systems	2015-06-29 13:48:44 +00:00