Hi all,
I am trying to display a large text into a vaadin text area. The purpose is to implement a tail like functionality so I can view the logs of an app live over HTTP.
My app is POSTing it’s logs every 2 seconds into a vaadin app where I update the content of a TextArea by appending the new logs. Under heavy load the app is posting large amount of logs in 2 seconds. The vaadin server side has no problem with dealing with this, the append to textarea operation takes under 100ms, but the vaadin client, in the browser freezes.
Does anyone have any suggestion how vaadin client could handle huge amount of text displayed?
p.s. I have tryed with a table also instead of a text area but the performance is much worse.
That would not help. Tee vaadin client uses a refresher to keep the client up to date. The refresh interval is around 5 sec. I guess that in 5 sec the number of messages or the size of them gets pretty big so the client spends some time to draw the UI. A quick fix, untill vaadin 7.1.0 (server push) I managed to add a custom refresher for my window with a lower refresh interval (0.5s). UI is still sluggy but it’s alot better. I guess that getting messages from the server every 0.5 sec does not allow them to accumulate in size or number.
Just FWIMC,
Fixed the sluggy UI by trimming down the number of logs to latest 3000 lines in a text area. Over this value vaadin client gets more and more unresponsive.