Its a little confusing question I believe . Actually there are two files X & Y. When I am reading X from its primary .I want to make sure simultaneous writing of Y should go to any other OSD except primary OSD for X (from where my current read is getting served ) . - Hemant Sural.e On Wed, Nov 21, 2012 at 11:50 AM, Sage Weil <sage@xxxxxxxxxxx> wrote: > On Wed, 21 Nov 2012, hemant surale wrote: >> >> and one more thing how can it be possible to read from one osd and >> >> then simultaneous write to direct on other osd with less/no traffic? >> > >> > I'm not sure I understand the question... >> >> Scenario : >> I have written file X.txt on some osd which is primary for filr >> X.txt ( direct write operation using rados cmd) . >> Now while read on file X.txt is in progress, Can I make sure >> the simultaneous write request must be directed to other osd using >> crushmaps/other way? > > Nope. The object location is based on the name. Reads and writes go to > the same location so that a single OSD can serialize request. That means, > for example, that a read that follows a write returns the just-written > data. > > sage > > >> Goal of task : >> Trying to avoid read - write clashes as much as possible to >> achieve faster operations (I/O) . Although CRUSH selects osd for data >> placement based on pseudo random function. is it possible ? >> >> >> >> - >> Hemant Surale. >> >> >> >> On Tue, Nov 20, 2012 at 10:15 PM, Sage Weil <sage@xxxxxxxxxxx> wrote: >> > On Tue, 20 Nov 2012, hemant surale wrote: >> >> Hi Community, >> >> I have question about port number used by ceph-osd daemon . I >> >> observed traffic (inter -osd communication while data ingest happened) >> >> on port 6802 and then after some time when I ingested second file >> >> after some delay port no 6804 was used . Is there any specific reason >> >> to change port no here? >> > >> > The ports are dynamic. Daemons bind to a random (6800-6900) port on >> > startup and communicate on that. They discover each other via the >> > addresses published in the osdmap when the daemon starts. >> > >> >> and one more thing how can it be possible to read from one osd and >> >> then simultaneous write to direct on other osd with less/no traffic? >> > >> > I'm not sure I understand the question... >> > >> > sage >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
