func init() {
http.HandleFunc("/", handler)
}
在处理函数中，有代码迭代数据列表、处理数据并聚合结果。
假设对于给定的查询，有 100 个项目需要处理。对于我将日志写入 Appengine 控制台的每个项目，“项目 n 已被处理”。
这是问题所在：
请求不返回。前 40 个左右项目的日志消息，然后它会重复，然后重复。它总是停止是相同的项目，然后重新启动。
我最好的猜测是应用程序正在达到内存限制或其他东西，而 Appengine Go 运行时只是重新启动，并重新执行处理程序。
对于一小部分项目，处理按预期进行，并且日志不显示任何循环。
请求日志中没有错误，但另一个日志显示：
panic: poll_ctl
goroutine 3 [running]:
runtime/eventloop.(*pollServer).ctlfd(0x9035f8, 0x204100000005, 0x3, 0x2041, 0x0, ...)
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:428 +0xdf
runtime/eventloop.(*pollServer).loop(0x9035f8, 0x0)
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:411 +0x4d8
created by runtime/eventloop.init·1
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:232 +0x40
goroutine 1 [select (no cases)]:
appengine_internal/fd_transport.serveHTTP(0x7fff76502f58, 0x70615f2f00000002, 0x7fff76502f5b, 0x3, 0x7fff76502f6c, ...)
go/src/pkg/appengine_internal/fd_transport/fd_transport.go:44 +0x26b
appengine_internal.Main()
go/src/pkg/appengine_internal/internal.go:184 +0x1a8
main.main()
_go_main.go:16 +0x18
goroutine 2 [select]:
created by _
_.go:568 +0xd2
goroutine 10 [chan receive]:
runtime/eventloop.(*pollServer).wait(0x9035f8, 0xf840095a60, 0xf84011ac30, 0xb, 0x1, ...)
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:472 +0x1a7
runtime/eventloop.(*FD).ReadFrom(0xf840095a50, 0xf840138000, 0x7d0000007d0, 0xf800000000, 0x0, ...)
go/src/pkg/runtime/eventloop/fd.go:135 +0x1c2
created by _
_.go:144 +0x7a
goroutine 5 [chan receive]:
created by _
_.go:461 +0x3ca
goroutine 6 [semacquire]:
sync.runtime_Semacquire(0xf8408034d8, 0xf8408034d8)
go/src/pkg/runtime/zsema_amd64.c:146 +0x25
sync.(*Cond).Wait(0xf840096bb0, 0x1)
go/src/pkg/sync/cond.go:67 +0xaa
created by _
_.go:462 +0x3e1
goroutine 7 [chan receive]:
runtime/eventloop.(*pollServer).wait(0x9035f8, 0xf840095c70, 0xf84011ac30, 0xb, 0x1, ...)
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:472 +0x1a7
runtime/eventloop.(*FD).Read(0xf840095c60, 0xf84113a000, 0x972a80000000c, 0x2b5800000000, 0xf84011ac30, ...)
go/src/pkg/runtime/eventloop/fd.go:93 +0x18c
io.ReadAtLeast(0xf84012c0c0, 0xf840095c60, 0xf84113a000, 0x972a80000000c, 0x2b580000000c, ...)
go/src/pkg/io/io.go:254 +0xc3
io.ReadFull(0xf84012c0c0, 0xf840095c60, 0xf84113a000, 0x972a80000000c, 0xf840095c60, ...)
go/src/pkg/io/io.go:273 +0x69
created by _
_.go:845 +0x2c6
goroutine 11 [runnable]:
runtime/eventloop.(*pollServer).wait(0x9035f8, 0xf840095b10, 0xf84011ac30, 0xb, 0x1, ...)
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:472 +0x1a7
runtime/eventloop.(*FD).Accept(0xf840095b00, 0x0, 0x0, 0xf84011ac30, 0xb, ...)
go/src/pkg/runtime/eventloop/fd.go:72 +0x185
net/http.(*Server).Serve(0xf840129f00, 0xf8400cfa80, 0xf840095b00, 0x0, 0x0, ...)
go/src/pkg/net/http/server.go:1012 +0x88
net/http.Serve(0xf8400cfa80, 0xf840095b00, 0xf84012c090, 0xf8400e0b10, 0xf8400e0b10, ...)
go/src/pkg/net/http/server.go:977 +0x71
created by _
_.go:145 +0xe9
goroutine 12 [timer goroutine (idle)]:
created by addtimer
go/src/pkg/runtime/ztime_amd64.c:70
goroutine 13 [runnable]:
runtime/eventloop.(*pollServer).wait(0x9035f8, 0xf8400959b0, 0xf84011ac30, 0xb, 0x1, ...)
go/src/pkg/runtime/eventloop/poll_linux_amd64.go:472 +0x1a7
runtime/eventloop.(*FD).Read(0xf8400959a0, 0xf840139000, 0x100000001000, 0x0, 0xf84011ac30, ...)
go/src/pkg/runtime/eventloop/fd.go:93 +0x18c
io.(*LimitedReader).Read(0xf840123580, 0xf840139000, 0x100000001000, 0xf8900000000, 0x0, ...)
go/src/pkg/io/io.go:394 +0xc1
bufio.(*Reader).fill(0xf840129f80, 0x2b5853e92000)
go/src/pkg/bufio/bufio.go:77 +0xf0
bufio.(*Reader).Read(0xf840129f80, 0xf84013d000, 0x27100000000c, 0xc, 0x0, ...)
go/src/pkg/bufio/bufio.go:142 +0x188
io.ReadAtLeast(0xf84012c600, 0xf84012c570, 0xf84013d000, 0x27100000000c, 0xc, ...)
go/src/pkg/io/io.go:254 +0xc3
io.ReadFull(0xf84012c600, 0xf84012c570, 0xf84013d000, 0x27100000000c, 0xf84012c570, ...)
go/src/pkg/io/io.go:273 +0x69
net/http.(*conn).serve(0xf8401320c0, 0x0)
go/src/pkg/net/http/server.go:656 +0x621
created by net/http.(*Server).Serve
go/src/pkg/net/http/server.go:1040 +0x430
goroutine 59 [sleep]:
time.Sleep(0x5dfdee1, 0xf8408034d0)
go/src/pkg/runtime/ztime_amd64.c:22 +0x49
created by _
_.go:791 +0xc4
goroutine 15 [chan receive]:
也许我没有记录所有错误，但即使，什么可能导致循环？
更新 近乎无休止的循环很快耗尽了我的数据存储写入配额，现在我收到了一个正在记录的无报价错误。在错误日志之后，再次调用处理程序。然后再次....
func handleError(w http.ResponseWriter, c appengine.Context, err error) {
c.Infof("ERROR")
c.Errorf("ERROR datastore: %s", err.Error())
}
...
rk, err := datastore.Put(c, rk, e)
if err != nil {
handleError(w, c, err)
return
}
更新 2 切换到 f4 实例后，代码按预期运行。我仍然认为 Appengine Go 运行时由于某种原因（内存）静默失败，并重新启动处理程序执行。这是我最好的猜测，我不知道。