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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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1b228c98ce
Regression introduced with 8.4.5 drbd: application writes may set-in-sync in protocol != C Overwriting the same block (LBA) while a former version is still "in-flight" to the peer (to be exact: we did not receive the P_BARRIER_ACK for its epoch yet) would wait for the full epoch of that former version to be acknowledged by the peer. In synchronous and quasi-synchronous protocols C and B, this may double the latency on overwrites. With protocol A, which is supposed to be asynchronous and only wait for local completion, it is even worse: it would make overwrites quasi-synchronous, they would be hit by the full RTT, which protocol A was specifically meant to avoid, and possibly the additional time it takes to drain the buffers first. Particularly bad for databases, or anything else that does frequent updates to the same blocks (various file system meta data). No impact if >= rtt passes between updates to the same block. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com> |
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| .. | ||
| drbd_actlog.c | ||
| drbd_bitmap.c | ||
| drbd_debugfs.c | ||
| drbd_debugfs.h | ||
| drbd_int.h | ||
| drbd_interval.c | ||
| drbd_interval.h | ||
| drbd_main.c | ||
| drbd_nl.c | ||
| drbd_nla.c | ||
| drbd_nla.h | ||
| drbd_proc.c | ||
| drbd_protocol.h | ||
| drbd_receiver.c | ||
| drbd_req.c | ||
| drbd_req.h | ||
| drbd_state_change.h | ||
| drbd_state.c | ||
| drbd_state.h | ||
| drbd_strings.c | ||
| drbd_strings.h | ||
| drbd_vli.h | ||
| drbd_worker.c | ||
| Kconfig | ||
| Makefile | ||