Rob Ross wrote:
Regarding Peter Staubach's comments about no one ever using the readdirplus() call; well, if people weren't performing this workload in the first place, we wouldn't *need* this sort of call! This call is specifically targeted at improving "ls -l" performance on large directories, and Sage has pointed out quite nicely how that might work.
I don't think that anyone has shown a *need* for this sort of call yet, actually. What application would actually benefit from this call and where are the measurements? Simply asserting that "ls -l" will benefit is not enough without some measurements. Or mention a different real world application... Having developed and prototyped the NFSv3 READDIRPLUS, I can tell you that the wins were less than expected/hoped for and while it wasn't all that hard to implement in a simple way, doing so in a high performance fashion is much harder. Many implementations that I have heard about turn off READDIRPLUS when dealing with a large directory. Caching is what makes things fast and caching means avoiding going over the network. ps - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html