Arroz Posted November 14, 2009 Report Share Posted November 14, 2009 Hello, I finally installed Retrospect 8 at home, and I'm testing it. I have a few questions about this, feel free to answer. 1) Are there docs? 2) Where do the AES 256 key/password gets stored? In the system preferences, or in the media set? I hope it's not in the media set, it would be pointless. 3) How does grooming work exactly? I have 3 machines backing up to the same media set. I configured grooming to 90 backups. Is this 90 backups of *each* machine, or 90 backups total? How can I make sure a backup of a machine that's not backed up for a few days won't be deleted? And what's the "Retrospect policy" in the grooming options? Yours Miguel Arroz Quote Link to comment Share on other sites More sharing options...
Arroz Posted November 14, 2009 Author Report Share Posted November 14, 2009 Hi! Another one: how intelligent is grooming? Say I have file A and file B. File A changes every day, file B never changes. The initial backup will backup A and B. All the subsequent backups will only backup A. When the oldest backup grooming day arrives, what happens to B? I suppose it's not deleted, but just checking... Yours Miguel Arroz Quote Link to comment Share on other sites More sharing options...
rhwalker Posted November 15, 2009 Report Share Posted November 15, 2009 miguel, there is no documentation for Retrospect 8 other than the Getting Started Guide. Retrospect documentation It's only been about a year since the product was announced. Retrospect grooms by snapshots, which is the Retrospect paradigm. Read up a little on snapshots. Oh, forgot, there is no documentation. russ Quote Link to comment Share on other sites More sharing options...
Arroz Posted November 15, 2009 Author Report Share Posted November 15, 2009 Hi! I know what snapshots are, I still have the version 6 manual here. I just wanted to confirm that grooming "merges" snapshots. ie, if the oldest snapshot is groomed, the second oldest snapshot (which will turn to be the oldest) contains *all* the files that were on the drive at the time of the second snapshot, and not just few files made on the incremental backup that lead to the existence of the second snapshot. BTW, what the heck is Retrospect code doing with my CPUs? I have one of my two G5 2 Ghz CPUs being eaten by 100%, and I can't to better than 200 MB/minute... I'm using AES 256, ok, but damn it, my laptop has PGP installed (that does AES 256 on the fly trough the entire disk surface) and I can't feel any performance hit. I expected this version to be much faster than before, but looks like I was wrong. And the fact that I'm using PowerPC is not an excuse, the G5s are fast enough to be able to crunch AES 256 much faster than this. Yours Miguel Arroz Quote Link to comment Share on other sites More sharing options...
rhwalker Posted November 16, 2009 Report Share Posted November 16, 2009 I know what snapshots are, I still have the version 6 manual here. Respectfully, Miguel, you don't understand what snapshots are, at least from your restated question: I just wanted to confirm that grooming "merges" snapshots. ie, if the oldest snapshot is groomed, the second oldest snapshot (which will turn to be the oldest) contains *all* the files that were on the drive at the time of the second snapshot, and not just few files made on the incremental backup that lead to the existence of the second snapshot. There is no "merging" of snapshots by grooming. See my earlier post in another thread for an explanation: Snapshots and grooming with the Retrospect paradigm And the fact that I'm using PowerPC is not an excuse, the G5s are fast enough to be able to crunch AES 256 much faster than this. Yes it is both the excuse and the problem. A design decision was made with Retrospect 8 to have the media set data structure be that for little endian (Intel) architectures rather than that for big endian (PowerPC) architectures. A lot of CPU time is spent swapping the bytes back and forth from the Intel format of the data structures and the PowerPC format used internally by your G5 Retrospect program. Russ Quote Link to comment Share on other sites More sharing options...
Arroz Posted November 16, 2009 Author Report Share Posted November 16, 2009 (edited) Hi! I do understand what snapshots are. But, given the overall product quality, I really wanted to make sure that it did "the right thing", as it's not obvious if the feature was correctly implemented or not (we are talking about a product that stops restoring backups when the DST changes, so I hope you understand my lack of trust in it). Anyway, your sentence "Grooming, depending on the options you have chosen, picks a number of recent "snapshots" and then retains only those files in the database that are necessary to support those snapshots, and removes all files that are not referenced by those snapshots, and then compacts the database." makes it perfectly clear. About the PowerPC problem, I understand things have to be designed for supporting future machines and not the past ones, but damn it... I'm a software developer myself. Retrospect is essentially reading raw data from one end and writing it in the other. The vast majority of data is the file contents (which are not affected by any byte endian issue), a very small part of it is byte-order sensitive data. How the heck can it be so slow, almost to the point of being unusable, on a very fast machine like the G5? Yours Miguel Arroz Edited November 16, 2009 by Guest Quote Link to comment Share on other sites More sharing options...
rhwalker Posted November 16, 2009 Report Share Posted November 16, 2009 But, given the overall product quality, I really wanted to make sure that it did "the right thing", as it's not obvious if the feature was correctly implemented or not (we are talking about a product that stops restoring backups when the DST changes, so I hope you understand my lack of trust in it). Retrospect 8 is not without bugs, and I made no comment as to whether grooming "did the right thing." There are occasional reports in the Windows forums about grooming corrupting a backup set. As you can expect, it's a complex process. Anyway, your sentence "Grooming, depending on the options you have chosen, picks a number of recent "snapshots" and then retains only those files in the database that are necessary to support those snapshots, and removes all files that are not referenced by those snapshots, and then compacts the database." makes it perfectly clear. That's how it is supposed to work when bugs aren't present. About the PowerPC problem, I understand things have to be designed for supporting future machines and not the past ones, but damn it... I'm a software developer myself. Retrospect is essentially reading raw data from one end and writing it in the other. The vast majority of data is the file contents (which are not affected by any byte endian issue), a very small part of it is byte-order sensitive data. How the heck can it be so slow, almost to the point of being unusable, on a very fast machine like the G5? I wasn't trying to defend the performance, just to report how it is. Realize that all of the matching comparisons and sortings have to be done on the internal data structures, which means a lot of byte swapping of data structures from the backup set. Also realize that Retrospect 8 is very immature. To my mind, it's important to get the program working correctly before performance enhancements are done. It's of little importance if the program screws up fast. Performance, by and large, is an algorithm issue, solved by design, although low-level optimization of critical loops can have dramatic effect. I have no knowledge of whether a design review was conducted of Retrospect 8. Sometimes I wonder. Russ Quote Link to comment Share on other sites More sharing options...
Arroz Posted November 16, 2009 Author Report Share Posted November 16, 2009 (edited) Hi! You're right about the fact that correction comes before performance in software developing. However, as any "rule" of this kind, some common sense must apply. It's not good to ship a product that works (?) but it's so slow that it's unusable in practice. I would understand that my old G4 at 450 Mhz would take more than 24 hours to backup my laptop. I don't understand how can a dual 2 Ghz G5 do that, specially when I know that it's doing less than 200 MB/minute. Oh well, at least we have decent encryption now. I guess we can't have everything. I expected Retrospect 8 to be much better than this, specially taking into consideration the time it took to be released. But serious bugs, poor performance, and a lot of UI problems turn it from "the best backup software out there" to "huh, unfortunately, there's nothing better than this". Yours Miguel Arroz Edited November 16, 2009 by Guest Quote Link to comment Share on other sites More sharing options...
rhwalker Posted November 16, 2009 Report Share Posted November 16, 2009 I expected Retrospect 8 to be much better than this, specially taking into consideration the time it took to be released. You are making the assumption that there was ongoing development all that time, which may not be true. There are those of us who believe that the product was abandoned and then resurrected. Retrospect 8 should be viewed as a work in progress. If I had been the product manager, and considering Apple's drop in support for PowerPC, I probably would not have included PowerPC support in the Retrospect engine, and would have ended that with Retrospect 6. I would, however, have made reading of older backup sets (back to Retrospect 2.0, at least) by Retrospect 8 a priority. I suspect that a lot of time has been spent chasing byte-swapping bugs, etc., in the PowerPC version, and in testing and supporting the two versions. Russ Quote Link to comment Share on other sites More sharing options...
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