mysql driver freeze, and hang the query progress,Does this normal?

[ghost]

here is strace output

{{EPOLLIN|EPOLLOUT, {u32=1179919736, u64=140029998671224}}}, 128, -1) = 1
12:01:55 futex(0xc820028e90, FUTEX_WAKE, 1) = 1
12:01:55 futex(0x7ea700, FUTEX_WAKE, 1) = 1
12:01:55 futex(0x7ea640, FUTEX_WAKE, 1) = 1
12:01:55 read(103, "\f\0\0\1\0\2\0\0\0\1\0\1\0\0\0\0\27\0\0\2\3def\0\0\0\1?\0\f?"..., 4096) = 89
12:01:55 write(103, "\26\0\0\0\27\2\0\0\0\0\1\0\0\0\0\1\10\0\313\234\n\0\0\0\0\0", 26) = 26
12:01:55 read(103, 0xc82026f000, 4096)  = -1 EAGAIN (Resource temporarily unavailable)
12:01:55 futex(0x7eadd0, FUTEX_WAIT, 0, NULL

) = 0

[ghost]

[pid  5951] 12:25:56 futex(0xc820028e90, FUTEX_WAIT, 0, NULL <unfinished ...>
[pid  5949] 12:25:56 <... select resumed> ) = 0 (Timeout)
[pid  5949] 12:25:56 futex(0x7ea700, FUTEX_WAIT, 0, {60, 0} <unfinished ...>
[pid  5948] 12:25:56 <... epoll_wait resumed> {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616539456, u64=140597370974016}}}, 128, -1) = 1
[pid  5948] 12:25:56 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616539264, u64=140597370973824}}}, 128, -1) = 1
[pid  5948] 12:25:56 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616539072, u64=140597370973632}}}, 128, -1) = 1
[pid  5948] 12:25:56 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616538880, u64=140597370973440}}}, 128, -1) = 1
[pid  5948] 12:25:56 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616538688, u64=140597370973248}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616538496, u64=140597370973056}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616538304, u64=140597370972864}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616538112, u64=140597370972672}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616537920, u64=140597370972480}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616537728, u64=140597370972288}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616537536, u64=140597370972096}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1616537344, u64=140597370971904}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584771064, u64=140597339205624}}}, 128, -1) = 1
[pid  5948] 12:25:57 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584770872, u64=140597339205432}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584770680, u64=140597339205240}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584770488, u64=140597339205048}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584770296, u64=140597339204856}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584770104, u64=140597339204664}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584769912, u64=140597339204472}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584769720, u64=140597339204280}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584769528, u64=140597339204088}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584769336, u64=140597339203896}}}, 128, -1) = 1
[pid  5948] 12:25:58 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584769144, u64=140597339203704}}}, 128, -1) = 1
[pid  5948] 12:25:59 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584768952, u64=140597339203512}}}, 128, -1) = 1
[pid  5948] 12:25:59 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584768760, u64=140597339203320}}}, 128, -1) = 1
[pid  5948] 12:25:59 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584768568, u64=140597339203128}}}, 128, -1) = 1
[pid  5948] 12:25:59 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=1584768376, u64=140597339202936}}}, 128, -1) = 1
[pid  5948] 12:25:59 epoll_wait(4, {{EPOLLIN|EPOLLOUT|EPOLLRDH

[ghost]

[pid 23383] 15:28:21 futex(0x814080, FUTEX_WAIT, 0, NULL <unfinished ...>
[pid 23382] 15:28:21 restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid 23387] 15:28:21 futex(0xc820025790, FUTEX_WAIT, 0, NULL <unfinished ...>
[pid 23386] 15:28:21 futex(0xc8200a0110, FUTEX_WAIT, 0, NULL <unfinished ...>
[pid 23385] 15:28:21 epoll_wait(4,  <unfinished ...>
[pid 23384] 15:28:21 futex(0xc820024e90, FUTEX_WAIT, 0, NULL <unfinished ...>
[pid 23373] 15:28:21 futex(0x7f0010, FUTEX_WAIT, 0, NULL <unfinished ...>
[pid 23382] 15:29:05 <... restart_syscall resumed> ) = -1 ETIMEDOUT (Connection timed out)
[pid 23382] 15:29:05 select(0, NULL, NULL, NULL, {0, 20}) = 0 (Timeout)
[pid 23382] 15:29:05 futex(0x7ef720, FUTEX_WAIT, 0, {60, 0}) = -1 ETIMEDOUT (Connection timed out)
[pid 23382] 15:30:05 select(0, NULL, NULL, NULL, {0, 20}) = 0 (Timeout)
[pid 23382] 15:30:05 futex(0x7ef720, FUTEX_WAIT, 0, {60, 0}

[methane]

You don't write about what did you do.
No one can say about it's normal or not.

[ghost]

The common DB.Query, DB.Exec sql command.

nothing serious

[methane]

strace output you wrote looks very common for Go's runtime.

What query do you send?
Have you tried same query from mysql cli? How long it takes?

[ghost]

I am wrote the same program using php, it works well with mysql.
The golang version program will freeze after a while.
The connection seems broken, but not disconnected. so we can not handle the hangs up.

[methane]

I am wrote the same program using php, it works well with mysql.

No one verify it until you share reproducible sample code.

The connection seems broken,

Why? There are only two lines about mysql in your strace.

12:01:55 read(103, "\f\0\0\1\0\2\0\0\0\1\0\1\0\0\0\0\27\0\0\2\3def\0\0\0\1?\0\f?"..., 4096) = 89
12:01:55 write(103, "\26\0\0\0\27\2\0\0\0\0\1\0\0\0\0\1\10\0\313\234\n\0\0\0\0\0", 26) = 26

First line is receiving OK packet. You should be able to fetch results if your program doesn't have bugs.
Second line tells mysql driver sends something. But it seems not a valid mysql packet.
Parhaps, you forgot -f option of strace. Since there are no [pid xxxx] prefix in your first post.

Another strace output are meaningless. futex and epoll_wait is used in Go's runtime.
It's not relating to mysql.

[ghost]

this package, mysql go sql driver using network library to communicate mysql server via tcp protocol.
The problems was : the connection broken , but there is no way to set read timeout / wait timeout at our client side.
so if not success read here, lead connection hangs up.

[ghost]

[pid 23382] 15:29:05 <... restart_syscall resumed> ) = -1 ETIMEDOUT (Connection timed out)

As strace output said. the connection already timed out.
so we should close the connection , but currently we have no way to terminate the connection

[ghost]

I hope the IPConn.SetReadDeadline will helpful with my situation.
https://golang.org/pkg/net/#IPConn.SetReadDeadline

[methane]

@netroby Your strace doesn't include which syscall returns ETIMEDOUT.

[pid 23382] 15:28:21 restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid 23382] 15:29:05 <... restart_syscall resumed> ) = -1 ETIMEDOUT (Connection timed out)

It may not be related to mysql connection.

[methane]

For example, futex may return ETIMEDOUT and it's not related TCP.
http://man7.org/linux/man-pages/man2/futex.2.html

[methane]

Your strace doesn't have important part.
I recommend you to use strace -f -s300 -e!futex,epoll_wait and report enough outout.

tcpdump is also good tool to know TCP state.

But, reporting reproducible code is best.