gaige Posted January 4, 2003 Report Share Posted January 4, 2003 I had occasion to watch a lengthy (multi-tape 80+GB) backup process today. Throughout the process, I periodically checked in to see what speeds I was seeing, etc. I noticed a few anomolies in the display that I don't belive have any bearing on reality but are very disconcerting: 1. Occasionally, the server will display G instead of M when backing up data. This happens sometimes when there is a large volume being backed up (<1GB) and the amount of data remaining dips below 1GB. It doesn't happen all of the time. 2. This one was a bit more of a concern. On the 17th volume of a 19 volume backup script, my backup said it was pushing 150MB/min on the volume being backed up, but the entire script was 21MB/min instead. This one doesn't make any sense to me, because as of the previous volume, it was 148MB/min. -Gaige Link to comment Share on other sites More sharing options...
AmyJ Posted January 15, 2003 Report Share Posted January 15, 2003 In reply to: 1. Occasionally, the server will display G instead of M when backing up data. This happens sometimes when there is a large volume being backed up (<1GB) and the amount of data remaining dips below 1GB. It doesn't happen all of the time. Yes, and when the amount of data to be backed up continued to get smaller, eventually you would see xxx M to be backed up. The program will adjust the display as needed. In reply to: 2. This one was a bit more of a concern. On the 17th volume of a 19 volume backup script, my backup said it was pushing 150MB/min on the volume being backed up, but the entire script was 21MB/min instead. This one doesn't make any sense to me, because as of the previous volume, it was 148MB/min. The total performance is going to be an average of all 19 volumes. The performance per volume that you see on in the execution window while a backup is running is dynamic - the number will change based on the variables - speed of source, type of file being copied, etc. Link to comment Share on other sites More sharing options...
gaige Posted January 15, 2003 Author Report Share Posted January 15, 2003 Pardon me, I thought it would be patently obvious from the word ANOMOLOUS in my original post, that it was INCORRECTLY displaying G instead of M in the window. As in, 19GB to back up.... 17GB... 2GB...500GB...42GB (note how the last one does not make any sense at all?). It doesn't adjust the display as needed, it leaves it as G unnecessarilly at times, causing confusion to the user base (especially when I don't have 500GB on any one volume. In reply to: ------------------------ Yes, and when the amount of data to be backed up continued to get smaller, eventually you would see xxx M to be backed up. The program will adjust the display as needed. PART TWO ---- Let's go through the math on this one. 19 volume backup script. Total of 60GB of backups. At volume 16, the server is claiming that it is running at 148MB/minute for the entire backup. At volume 17, the server is claiming 150MB/min for that backup and 21MB/min for the entire backup. This is clearly not possible, so there's a bug somewhere. As a mathematical example, if 50GB had been backed up at 148MB/min and the current reading is 150MB/min, it wouldn't be possible for the averages to come down to 21MB/min within any reasonable period of time. It takes 4.8 hrs to back up 50GB at 148MB/minute. For the entire backup to have been at 21MB/minute, the 60GB backup would have taken 48 hours, which I assure you it did not. In reply to: -------------------------------------------------------------------------------- 2. This one was a bit more of a concern. On the 17th volume of a 19 volume backup script, my backup said it was pushing 150MB/min on the volume being backed up, but the entire script was 21MB/min instead. This one doesn't make any sense to me, because as of the previous volume, it was 148MB/min. -------------------------------------------------------------------------------- The total performance is going to be an average of all 19 volumes. The performance per volume that you see on in the execution window while a backup is running is dynamic - the number will change based on the variables - speed of source, type of file being copied, etc. Can't find the answer? Try here next... Link to comment Share on other sites More sharing options...
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