microsecond resolution
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I've sourced stackoverflow, the docs, and the web but I can't figure out: does flink support microsecond timestamp resolution? Thanks!
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Yes. It does.
See: https://ci.apache.org/projects/flink/flink-docs-release-1.1/apis/streaming/event_timestamps_watermarks.html#assigning-timestamps "Both timestamps and watermarks are specified as millliseconds since the Java epoch of 1970-01-01T00:00:00Z." -Matthias On 12/04/2016 10:57 AM, jeff jacobson wrote: > I've sourced stackoverflow, the docs, and the web but I can't figure > out: does flink support microsecond timestamp resolution? Thanks! |
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Sorry if I'm missing something. That link mentions milliseconds, no? My question is whether or not I can specify microseconds where 1000microseconds = 1millisecond. Thanks! On Sun, Dec 4, 2016 at 5:05 PM, Matthias J. Sax <[hidden email]> wrote: Yes. It does. |
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Hash: SHA512 Oh. My bad... Did not read your question carefully enough. Than the answer is no, it does not support microseconds (only milliseconds). - -Matthias On 12/4/16 2:22 PM, jeff jacobson wrote: > Sorry if I'm missing something. That link mentions milliseconds, > no? My question is whether or not I can specify microseconds where > 1000microseconds = 1millisecond. Thanks! > > On Sun, Dec 4, 2016 at 5:05 PM, Matthias J. Sax <[hidden email] > <mailto:[hidden email]>> wrote: > > Yes. It does. > > See: > https://ci.apache.org/projects/flink/flink-docs-release-1.1/apis/strea > > <https://ci.apache.org/projects/flink/flink-docs-release-1.1/apis/stream ing/event_timestamps_watermarks.html#assigning-timestamps> > > "Both timestamps and watermarks are specified as millliseconds > since the Java epoch of 1970-01-01T00:00:00Z." > > > > -Matthias > > > On 12/04/2016 10:57 AM, jeff jacobson wrote: >> I've sourced stackoverflow, the docs, and the web but I can't >> figure out: does flink support microsecond timestamp resolution? >> Thanks! > > Comment: GPGTools - https://gpgtools.org iQIYBAEBCgAGBQJYRJhUAAoJELz8Z8hxAGOiNKoP32ChGeNd7N8Zco2q6lsu+Hxd JZq62ey3wTrIUS+3oRlILwnu81cViQHtMMVBly3+YnqB85gNiaEUxEQTQCdKPl8G AqxoFIkMcrKGzwGXigKnCAoVIiyuPeNuhY1d1yv4rWrkt7qb0lCC02Xoq1C0hoS6 Stwk62GXmNRXPYpyjnSq/iAIMbjWaU+ZU0t4V3J8loroNuJ5QcUsJLfRXeo3/5ho f42L+IANyB5K7vnTxNZYyf5ShNVbTY9/iFaviluxrCNztqGTo7CxMpcyWyMS3wcF ycXcq/daB+guEJpW0sm4JtMPSsQ/kN99c/ig3t0HX1kDV7xrDDSF2qPvbYOWF38n omTr7RY3YRFi5LOKvBGa96Aw5UYjMddjcqozWId6xgdXfvz6RUeJCWa9RW8I6ptg 8TaJpM2WgDJMgMuzdl8dDv65l78DkLlNlNo53O66b/9Pt78P75KNjj8naD5kkj4C i9amwnUNNEnZucA2/1vhzr6cVSzrzBLL7juVj0VmABZo4itUZjjR0UkN7MB+ioWU trNhaXgE6EP/160n6D0/NUu02prm3jq8mK6gu9lZFWGbAeCUcch+CbvWSaiXAw3H BOieCsgZD1wfXQJ3wEmnqj/YP94uDlx1IjynskDevjk6OIyIysbBSIqgsUK6fvQ8 ztXO6ls7ARMOBmA= =/O+Q -----END PGP SIGNATURE----- |
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Help Matthias Abdallah. On Dec 4, 2016 11:27 PM, "Matthias J. Sax" <[hidden email]> wrote: -----BEGIN PGP SIGNED MESSAGE----- |
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In reply to this post by Matthias J. Sax-2
Wow. Really? Is there a way to do micros? A hack? A Jira story? Most (all?) U.S. equity and European futures, options, and stock markets timestamp in microseconds. This makes Flink unusable for a massive industry vertical. To the extent lower-frequency time-series data is being used (e.g. end of data prices), stream processing is kind of overkill. Love everything I've read about Flink...there's got to be a way to make this work, no? On Sun, Dec 4, 2016 at 5:27 PM, Matthias J. Sax <[hidden email]> wrote: -----BEGIN PGP SIGNED MESSAGE----- |
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Hi Jeff,
Actually in Flink timestamps are simple longs. This means that you can assign anything you want as a timestamp, as long as it fits in a long. Hope this helps and if not, we can discuss to see if we can find a solution that fits your needs together. Cheers, Kostas
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Thanks Kostas. So if we're comfortable treating timestamps as longs (and doing conversions to human readable time at our application level), we can use CEP, ML lib etc. in addition to all basic Flink functions? That's great news? To Matthias's point, why then does the following not read "Both timestamps and watermarks are specified as longs"? Before I go headlong into developing on Flink, I just want to be sure I'm covered here. Again, thanks. (The Youtube videos from FlinkForward are also great, btw. Incredibly impressed with Data Artisans.) https://ci.apache.org/ "Both timestamps and watermarks are specified as milliseconds since the Java epoch of 1970-01-01T00:00:00Z." On Mon, Dec 5, 2016 at 4:57 AM, Kostas Kloudas <[hidden email]> wrote:
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@Jeff - good point about the docs.
I think Kostas is right though - the event timestamps are up to the user's interpretation. The built-in window assigners interpret them as "Unix Epoch Millis", but you can define your own window assigners that interpret the timestamps differently. The system interprets them as also as Unix Epoch Millis when mixing event time and processing time (because processing time comes from System.currentTimeMillis()) So, you can "re-interpret" them by using custom window assigners and not using processing time. If you want to use a processing time like component, I'd suggest to incorporate that in your watermark generator. Stephan On Mon, Dec 5, 2016 at 1:05 PM, jeff jacobson <[hidden email]> wrote:
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Hi Jeff,
As Stephan said the interpretation of the timestamps is up to the logic of your job. And as for the documentation, thanks for reporting this. We should update it. Cheers, Kostas
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Thanks for clearing things up, Stephan and Kostas On Mon, Dec 5, 2016 at 8:08 AM, Kostas Kloudas <[hidden email]> wrote:
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Hi, If you set your stream to use event time (i.e. env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime); ) I think you can use all functions in the system without modification. So there is no need for any custom window assigners. If you then put microseconds into the timestamp field the you MUST make sure you do the same with things like watermarks. And if you want to have a watermark that is 5 seconds before the current time stamp you must be sure to substract 5000000 instead of 5000 fom the timestamp. Niels Basjes On Mon, Dec 5, 2016 at 2:48 PM, jeff jacobson <[hidden email]> wrote:
Best regards / Met vriendelijke groeten,
Niels Basjes |
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