It isn't clear to me at all on how you profile.. and in general, adding an entry will only write to ledger file's buffer, which if it takes 200+ms, there should be something wrong with your environment.
could you explain following: - what is your setup of your bookkeeper cluster? what is the configuration of your bookies and clients? - how you configure writing journal file to memory? - how you profile to get the time of writing to journal & writing to ledger file? if you made code change, please show us your code change. - what is the throughput (entries/sec) of your test? what is the configuration? - Sijie On Tue, Aug 26, 2014 at 9:35 AM, Jaln <[email protected]> wrote: > I write the journal file to memory, which cost 1.6ms, and the ledger file > to disk, > it cost 200+ ms. > > > On Tue, Aug 26, 2014 at 11:19 AM, Sijie Guo <[email protected]> wrote: > > > Could you explain how you profile the time? The ledger device isn't the > > dominated factor, The journal device is. > > > > - Sijie > > > > > > On Tue, Aug 26, 2014 at 9:13 AM, Jaln <[email protected]> wrote: > > > > > Hi Sijie, > > > Thanks, > > > One of my result is > > > entrysize: 1k > > > Throttle: 10k > > > Latency is 1324.1137182178 ms > > > I also profile the time and find that the ledger device can contribute > > > 232 ms. > > > > > > I don't think the ledger device should cause any cost. > > > > > > Jialin > > > > > > > > > On Tue, Aug 26, 2014 at 10:59 AM, Sijie Guo <[email protected]> > wrote: > > > > > > > The latency I think is between the client added the message and > > received > > > > acknowledge from quorum of bookies. Journal device will significantly > > > > affect the latency, Ledger device might slightly affect but not too > > much > > > > (it depends). If you are using only one disk for both ledger & > journal > > > > devices, you will definitely get really bad disk behavior. > > > > > > > > At the mean time, your configuration on bookie journal (e.g. group > > commit > > > > interval, commit buffer) will also affect the latency. > > > > > > > > So for your case, please specify your environment and configuration, > we > > > > will figure out why it takes to 2s. > > > > > > > > - Sijie > > > > > > > > > > > > On Tue, Aug 26, 2014 at 8:27 AM, Jaln <[email protected]> wrote: > > > > > > > > > Hi, > > > > > I'm running the bookkeeper benchmark on a single node, > > > > > The latency is about 2s using one disk. > > > > > I would like to know how this latency is calculated, > > > > > is the `latency' the time between "client sent the write msg" and > the > > > > > "write is committed on the journal devices and the ack code is > > > returned"? > > > > > > > > > > Does the ledger device affect the latency? Assuming ledger and > > journal > > > is > > > > > on > > > > > different disk. > > > > > > > > > > Best, > > > > > Jialin > > > > > > > > > > > > > > > > > > -- > > Genius only means hard-working all one's life >
