Go on utube and look up "Lighting smoker with pine straw".
Scott and Schawee did a great training video on how to light a smoker that lasts about 4-5 hours.
I held a class for our club after contestants lit their smokers for a smoker contest using their technique.
After 2 hours of sitting the other smokers were either close to being empty or only had about 30 minutes left at most. Then I opened up the smoker I did the training on. It looker like it had gone out, no smoke coming out. After a couple of puffs it was billowing smoke. I opened it up and showed that it was full of unburnt pine straw and put my hand in and touched the needles with the back of my fingers. They were only warm. I have found that after 4 hours you need to open it up and pack the needles back down again, there were still on lit needles in the top, if you still need it to keep smoking.
Try it I think you will like it. Every time I light a smoker with this technique, I have to put it out when I am done.