[pbs-devel] [PATCH proxmox-backup] fix #2983: improve tcp performance

[Dominik Csapak]

by leaving the buffer sizes on default, we get much better tcp performance
for high latency links

throughput is still impacted by latency, but much less so when
leaving the sizes at default.
the disadvantage is slightly higher memory usage of the server
(details below)

my local benchmarks (proxmox-backup-client benchmark):

pbs client:
PVE Host
Epyc 7351P (16core/32thread)
64GB Memory

pbs server:
VM on Host
1 Socket, 4 Cores (Host CPU type)
4GB Memory

average of 3 runs, rounded to MB/s
                    | no delay |     1ms |     5ms |     10ms |    25ms |
without this patch  |  230MB/s |  55MB/s |  13MB/s |    7MB/s |   3MB/s |
with this patch     |  293MB/s | 293MB/s | 249MB/s |  241MB/s | 104MB/s |

memory usage (resident memory) of proxmox-backup-proxy:

                    | peak during benchmarks | after benchmarks |
without this patch  |                  144MB |            100MB |
with this patch     |                  145MB |            130MB |

Signed-off-by: Dominik Csapak <d.csapak at proxmox.com>
---
 src/bin/proxmox-backup-proxy.rs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/bin/proxmox-backup-proxy.rs b/src/bin/proxmox-backup-proxy.rs
index 75065e6f..5844e632 100644
--- a/src/bin/proxmox-backup-proxy.rs
+++ b/src/bin/proxmox-backup-proxy.rs
@@ -87,8 +87,6 @@ async fn run() -> Result<(), Error> {
                     let acceptor = Arc::clone(&acceptor);
                     async move {
                         sock.set_nodelay(true).unwrap();
-                        sock.set_send_buffer_size(1024*1024).unwrap();
-                        sock.set_recv_buffer_size(1024*1024).unwrap();
                         Ok(tokio_openssl::accept(&acceptor, sock)
                             .await
                             .ok() // handshake errors aren't be fatal, so return None to filter
-- 
2.20.1