Messages in this thread | | | Date | Wed, 16 Nov 2005 12:56:36 -0800 (PST) | From | Kenny Simpson <> | Subject | Re: mmap over nfs leads to excessive system load |
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I tried the same test, but instead of ftruncate64, I simply did a pwrite64 to get the file extended... and got 40M+ with mostly outbound traffic, and much less CPU usage.....
Unfortunately, once my test file hit 4295065601, Bad Things (TM) started to happen. The system time went to 100% of a CPU, and the nfs traffic on that mount stopped.
I got an oprofile of the spinning system: samples % symbol name 301039 27.9748 zap_pte_range 156234 14.5184 unmap_vmas 111760 10.3856 __bitmap_weight 103624 9.6295 _spin_lock 97063 9.0198 unmap_page_range 67011 6.2272 unmap_mapping_range 59382 5.5182 sub_preempt_count 51258 4.7633 zap_page_range 25235 2.3450 page_address 16768 1.5582 unmap_mapping_range_vma 13257 1.2319 debug_smp_processor_id 11594 1.0774 add_preempt_count
I also seem unable to kill the test process.
Any ideas? (2**32 file size issue somewhere?)
-Kenny
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