projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 12bbb0d1 DL |
1 | .. SPDX-License-Identifier: GPL-2.0 |
| 2 | ||
| f9f52c34 | 3 | ========== |
| 12bbb0d1 | 4 | SMC Sysctl |
| f9f52c34 | 5 | ========== |
| 12bbb0d1 DL |
6 | |
| 7 | /proc/sys/net/smc/* Variables | |
| f9f52c34 | 8 | ============================= |
| 12bbb0d1 DL |
9 | |
| 10 | autocorking_size - INTEGER | |
| 11 | Setting SMC auto corking size: | |
| 12 | SMC auto corking is like TCP auto corking from the application's | |
| 13 | perspective of view. When applications do consecutive small | |
| 14 | write()/sendmsg() system calls, we try to coalesce these small writes | |
| 15 | as much as possible, to lower total amount of CDC and RDMA Write been | |
| 16 | sent. | |
| 17 | autocorking_size limits the maximum corked bytes that can be sent to | |
| 18 | the under device in 1 single sending. If set to 0, the SMC auto corking | |
| 19 | is disabled. | |
| 20 | Applications can still use TCP_CORK for optimal behavior when they | |
| 21 | know how/when to uncork their sockets. | |
| 22 | ||
| 23 | Default: 64K | |
| 4bc5008e WG |
24 | |
| 25 | smcr_buf_type - INTEGER | |
| 26 | Controls which type of sndbufs and RMBs to use in later newly created | |
| 27 | SMC-R link group. Only for SMC-R. | |
| 28 | ||
| 29 | Default: 0 (physically contiguous sndbufs and RMBs) | |
| 30 | ||
| 31 | Possible values: | |
| 32 | ||
| 33 | - 0 - Use physically contiguous buffers | |
| 34 | - 1 - Use virtually contiguous buffers | |
| 35 | - 2 - Mixed use of the two types. Try physically contiguous buffers first. | |
| 36 | If not available, use virtually contiguous buffers then. | |
| 77eee325 WG |
37 | |
| 38 | smcr_testlink_time - INTEGER | |
| 39 | How frequently SMC-R link sends out TEST_LINK LLC messages to confirm | |
| 40 | viability, after the last activity of connections on it. Value 0 means | |
| 41 | disabling TEST_LINK. | |
| 42 | ||
| 43 | Default: 30 seconds. | |
| 0227f058 TL |
44 | |
| 45 | wmem - INTEGER | |
| 46 | Initial size of send buffer used by SMC sockets. | |
| 0227f058 TL |
47 | |
| 48 | The minimum value is 16KiB and there is no hard limit for max value, but | |
| 49 | only allowed 512KiB for SMC-R and 1MiB for SMC-D. | |
| 50 | ||
| a1602d74 | 51 | Default: 64KiB |
| 0227f058 TL |
52 | |
| 53 | rmem - INTEGER | |
| 54 | Initial size of receive buffer (RMB) used by SMC sockets. | |
| 0227f058 TL |
55 | |
| 56 | The minimum value is 16KiB and there is no hard limit for max value, but | |
| 57 | only allowed 512KiB for SMC-R and 1MiB for SMC-D. | |
| 58 | ||
| a1602d74 | 59 | Default: 64KiB |
| f8e80fc4 GW |
60 | |
| 61 | smcr_max_links_per_lgr - INTEGER | |
| 62 | Controls the max number of links can be added to a SMC-R link group. Notice that | |
| 63 | the actual number of the links added to a SMC-R link group depends on the number | |
| 64 | of RDMA devices exist in the system. The acceptable value ranges from 1 to 2. Only | |
| 65 | for SMC-R v2.1 and later. | |
| 66 | ||
| 67 | Default: 2 | |
| 1f2c9dd7 GW |
68 | |
| 69 | smcr_max_conns_per_lgr - INTEGER | |
| 70 | Controls the max number of connections can be added to a SMC-R link group. The | |
| 71 | acceptable value ranges from 16 to 255. Only for SMC-R v2.1 and later. | |
| 72 | ||
| 73 | Default: 255 |