can't turn off activemq's temp storage

I want to test the producer flow control, but the message always go into the temp store, giving me no way to test.

I have set the tempUsage to 1kb.

        <tempUsage>
            <tempUsage limit="1 kb"/>
        </tempUsage>

And when activemq starting, I can see a log that seems fine:

Temporary Store limit is 0 mb, whilst the max journal file size for the temporary store is: 32 mb, the temp store will not accept any data when used.

But when I send one 50mb message, it still go into temp store:

PListStore:[D:\apache-activemq-5.14.4\bin\..\data\localhost\tmp_storage] initialized

How I can do to turn off temp storage?