pull mode consume history message very slow

[UnderTreeTech]

First I produce 1k msg to broker, then I run the examples/consumer/pull/pull.go code with minor changes (only start one goroutine to consume), just like

for i := 0; i < 1; i++ {
		go func() {
			for {
				pull()
			}
		}()
	}

There the consume rate is very slow, every pull will block about 25s. But if modify the suspend param to false at

rocketmq-client-go/consumer/pull_consumer.go

Line 445 in f4875c1

sysFlag := buildSysFlag(false, true, true, false)

the consume rate comes fast.

[wupeaking]

I have same issue.