os/bluestore: enlarege aligned_size avoid too many vector(> IOV_MAX) #18828
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src/os/bluestore/KernelDevice.cc
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| uint64_t aligned_size = block_size; | ||
| // Avoid after rebuild_aligned_size_and_memory, get_num_buffers() > IOV_MAX | ||
| if (bl.get_num_buffers() >= IOV_MAX && (len > (IOV_MAX * block_size))) { | ||
| aligned_size = ROUND_UP_TO(len / IOV_MAX, block_size); |
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what if len is not the multiple of (IOV_MAX * block_size)? i think it should be
ROUND_UP_TO(ROUND_UP_TO(len, IOV_MAX) / IOV_MAX, block_size)
src/os/bluestore/KernelDevice.cc
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| aligned_size = ROUND_UP_TO(len / IOV_MAX, block_size); | ||
| } | ||
| if (bl.rebuild_aligned_size_and_memory(aligned_size, block_size)) { | ||
| dout(20) << __func__ << " rebuilding buffer to be aligned" << dendl; |
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could you print out the aligned_size here also? i think it could help with the performance related diagnosis.
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update. |
src/os/bluestore/KernelDevice.cc
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| if ((!buffered || bl.get_num_buffers() >= IOV_MAX)) { | ||
| uint64_t aligned_size = block_size; | ||
| // Avoid after rebuild_aligned_size_and_memory, get_num_buffers() > IOV_MAX | ||
| if (bl.get_num_buffers() >= IOV_MAX && (len > (IOV_MAX * block_size))) { |
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to be more consistent, could you please remove the parenthesis around len > (IOV_MAX * block_size) ?
src/os/bluestore/KernelDevice.cc
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| // Avoid after rebuild_aligned_size_and_memory, get_num_buffers() > IOV_MAX | ||
| if (bl.get_num_buffers() >= IOV_MAX && (len > (IOV_MAX * block_size))) { | ||
| aligned_size = ROUND_UP_TO(ROUND_UP_TO(len, IOV_MAX) / IOV_MAX, block_size); | ||
| dout(5) << __func__ << " because too many buffers, using " << aligned_size |
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i am not quite sure about dout(5). is a large bl.get_num_buffers() an unusual thing and we should watch out? actually what i suggested in last comment is to print the aligned_size at the "rebuilding buffer to be aligned" line with dout(20).
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update. |
majianpeng
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Fixes: http://tracker.ceph.com/issues/21932 Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
Fixes: http://tracker.ceph.com/issues/21932
Signed-off-by: Jianpeng Ma jianpeng.ma@intel.com