Publish 1.6.3 will go out as a client update in the morning followed by a rolling server update. We have no planned grid downtime; each individual simulator will experience a brief downtime during the day in staggered fashion. The rolling update is schedule to begin at 8:00 AM and run until 11:00 AM
There won't be any warning when the server you are on updates. The state data of the simulator will auto-save and shutdown. The downtime should be less than 5 minutes. The only risk of content loss is to whatever uploads may be in progress at the exact time of the shutdown. It would be wise to save regularly into your inventory if you're concerned about something that you're building. Events in progress should be able to continue, but do run the risk of a brief interruption.
Following are the release notes for 1.6.3
Second Life 1.6.3(2) April 20, 2005
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* Fixed a problem introduced in 1.6.2 where audio would stop playing if Second Life was not the frontmost window.
* Fixed a known problem where clients were being disconnected if a residents inventory was large enough. Note: It may still be possible to get disconnected with extremly large amounts of objects in a single folder.
* Improved framerate when manipulating and searching larges amounts of inventory.
* Added a preference that allows the user to have SL muted while it is minimized.
* Fixed a bug that was causing a large number of server crashes.
* Fixed a problem where it was possible to create doubles of certain inventory items.
* Fixed a problem where it was possible to create multiple items with identical names in the contents of object.
* Fixed a known problem where clients were being disconnected if a residents inventory was large enough. Note: It may still be possible to get disconnected with extremly large amounts of objects in a single folder.
* Fixed a problem in the client where the default plywood texture could not be seen by some users.
* Improved client movement key responsiveness when the client has low framerate.
* The client will no longer freeze if an object has multiple items in its contents with the same name.
* The Help menu "Script Help" button now properly asks the user to confirm before launching browser.
* Objects that chat via llSay() once again emit the chat swirl, making it easier to find objects spamming the chat channel.
* Added more debugging code to help track down a client crash related to the Local Lighting preference.
* Fixed a client crash bug.
Known Issues:
* The audio preference that allows SL to be muted while minimized erroneously says "/Hidden"