Tengine kernel parameters

tengine Kernel parameters

tcp_max_syn_backlog:  16384

Maximum port backlog Kernel restrictions . This parameter limits Server application The maximum number of ports that can be set backlog value ( Corresponding to port syn_backlog and backlog The queue length ). The motivation is to limit... On servers with limited memory / Avoid application configuration backlog Value to run out of kernel memory . If the application settings backlog Greater than this value , The operating system will automatically limit it to this value .(tengine listen backlog : 2048)

tcp_abort_on_overflow: 0

When tcp Connected 3 After Lu shook hands , Put the connection in ESTABLISHED State and deliver to the application backlog When queuing , Will check the backlog Is the queue full . If it's full , The usual behavior is to restore the connection to SYN_ACK state , In order to create 3 The last way to shake hands ACK The false appearance of accidental loss of a bag —— In this way, it can be retransmitted after the client has timed out ACK —— To try to enter again ESTABLISHED state —— As a repair / Retry mechanism . If enabled tcp_abort_on_overflow It's checking that backlog When the queue is full , Direct hair RST Package to the client to terminate the connection —— At this point, the client program will receive 104 Connection reset by peer error .

tcp_tw_timeout:3

Same as below

tcp_max_tw_buckets ：600000

Same as below

4.14.0-1.0.0.2.el7

tcp_tw_timeout:3

timewait Connect the quick recovery , Enhance the ability to build companies

tcp_max_syn_backlog:30000

ditto

tcp_abort_on_overflow ：0

ditto

tcp_max_tw_buckets ：600000

timewait Maximum number of connections , Avoid sudden tw Too much , Enhance the ability to build companies