ext3 allocate-with-reservation latencies

From: Lee Revell
Date: Mon Apr 04 2005 - 22:55:12 EST


I can trigger latencies up to ~1.1 ms with a CVS checkout. It looks
like inside ext3_try_to_allocate_with_rsv, we spend a long time in this
loop:

ext3_test_allocatable (bitmap_search_next_usable_block)
find_next_zero_bit (bitmap_search_next_usable_block)
find_next_zero_bit (bitmap_search_next_usable_block)

ext3_test_allocatable (bitmap_search_next_usable_block)
find_next_zero_bit (bitmap_search_next_usable_block)
find_next_zero_bit (bitmap_search_next_usable_block)

etc.

Lee

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Description: application/bzip