- what is your setup of your bookkeeper cluster? what is the configuration of your bookies and clients?
I run bookkeeper on a single node. OS is ubuntu 12.04, 16G memory, 1TB SATA disk, 120G sata SSD Run ./bookkeeper localbookie 3 -c /conf/bk_server.conf then ./benchmark writes -entrysize 2048 -throttle 10000 Others are default configuration, only the journalDirectory and ledgerDirectories are changed. - how you configure writing journal file to memory? using ramfs to allocate a folder and file in 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. write journal to ramfs and ledger to ssd, cost 1.6 ms latency write journal to ramfs and ledger to hdd, cost 200 ms latency Therefore, I woud say `the ledger to hdd' cost about 200ms - what is the throughput (entries/sec) of your test? what is the configuration? Throughput is determined by the throttle, in this case, it's 9994 ops/sec Best, Jialin On Tue, Aug 26, 2014 at 11:51 AM, Sijie Guo <[email protected]> wrote: > 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 > > > -- Genius only means hard-working all one's life
