Conference 7.286::atarist

    peter,
    got  gemar201 from your account last week but I had no chance to unpack
    the File. I started the filetransfer with kermit and whack
    sucessfully but unpacking resulted in something like "bad table on
    ***.rsc".
    I would like to try gemar on an tk50 with SCSI-controller, (DEC-stuff-
    controller is seen as adaptec).
    Thank You in advance for any help
    
    Regards 
            Armin 
    
     

    Hello Armin, 
    
    did you also get lharc231.lzh? The archives in my account are all
    packed with the latest version of lharc, which is in a self extracting
    archive. Some other colleagues used it for unpacking CoNnect and
    everything worked OK, so you should have no difficulties.
    
    If it doesn't work, please call me at DTN 861-3687.
    
    Regards, Peter.

    
     I have GEMAR v2.0 (dated, I think, October 1993). Are there any
    major differences between v2.0 and 2.01? I notice that while v2.0
    comes with English RSC file and docs, the full manual has not yet
    been translated into English. Does v2.01 now include an English
    translation of the manual?
    
    TIA,
    
    Best Regards,
    Brian
    

    Hello Brian, 
    
    as I don't know the current status of the GEMAR distribution I'd
    suggest you contact the author, Steffen Engel, via MausNet under the
    internet address "[email protected]" (hopefully correct).
    
    Please don't send mails larger than 48kB to the MausNet.
    
    Regards, 
    
      Peter.

    
    Thanks Peter,
    	
    	I've taken a note for future reference, but in the meantime
    was just wondering if the complete manual had been translated
    in v2.01.
    	I don't have a tape streamer, but on having seen how powerfull
    and comprehensive GEMAR looks to be IMHO, I would really like to
    get one for backups.
    
    Thanks and Best Regards,
    Brian 
                         

    
    I really can recomend GEMAR in conjunction with a SCSI-streamer. It
    just perfectly suits my needs for backup: over the weekend I do a
    complete backup (150 MB in about 30 minutes) and every day there is
    my daily backup for about 2 minutes. For these two tasks I wrote a
    script which I put on my desktop. Simply doubleclicking the icon starts
    the process, and when finished the program automatically returns to the
    desktop.
    
    Bernd
    
    

    
     Thanks for the recommendation Bernd, - yes, I'm convinced this for
    me too is the way to go for backups.
    BTW, I read a very recent post on usenet from the author of GEMAR,
    saying that v2.01 is required for use with the Falcon and fixes a
    minor bug with Falcon SCSI code; appart from that, I understand the
    package is the same as v2.0
    
    Best Regards,
    Brian 

    
      I arranged to borrow a SCSI tape drive this weekend, and tried
    it with GEMAR and the LINK. It was a TZ86, and although more
    experimentation would be required to find the optimum values for
    streaming, I backed up 443MB in 1 hr 50 minutes with 
          Backup Buffer 110kB
          Max Read      100k
          Data Rate     1000kB/s
    
      I understand from the documentation that the supplied XFS driver
    enables the tape drive to be accessed as a 'virtual drive' - this
    could also be a very usefull feature.
      The TZ86 needs to be returned, so unfortunately I won't be able
    to experiment further with parameters, but on actually seeing GEMAR
    working, I'm more convinced than ever that a tape streamer is now
    top priority for next add-on :-)
    
    Best Regards,
    Brian
     

    
    re. -1
    
    Brian, do you use MultiTOS? Because XFS-drivers only work with
    MultiTOS...
    
    Bernd
    
    

    
    Hi Bernd, 
              I don't have MultiTOS with which to run the XFS drivers,
    but I thought the part in the docs. which indicate that the tape
    drive could be accessed via. the XFS driver as a 'Read Only'
    virtual drive, was an interesting feature. (Is this correct?)
    
    (I found that the XFS driver/MultiTos did not need to be installed for
    backups, and it was only necessary to enter the SCSI ID of the
    drive (and select 'Inquiry') in the Streamer Options dialogue
    box, and when 'load tape' was selected from the menu, the tape streamer
    icon became active, displaying 'DEC' in the icon label).
    
    Best Regards,
    Brian :-)
    
    
    
    
     

    
      I tried GEMAR with a TK50Z, and the following parameters gave good
    streaming results:
    
    In 'Streamer Commands' submenu: X Test Unit Ready
    				    X Mode Sense
    			            X Mode Select
    
    			              Wait Before SCSI    1 tick
    				      Wait After SCSI     1 tick
    
    Backup Parameters submenu:      X Time Before SCSI
    
    			              Backup Buffer 7kB
    				      Maximum Read  69kB
                                      Data Rate 45kB/s
    
    I found the above worked well in keeping the tape streaming and the
    top 'buffer rate' bar in the display full, with a cached 4MB 16MHz ST.
    I also found that the Backup parameter figures are critical in that
    a shift of 1kB either way makes a very significant difference.
    
    Best Regards,
    Brian
    

    Thanks Brian,
    
    I've forwarded your parameters to Steffen. 
    
    Indeed these parameters are *very* critical. When I found the numbers
    in .0, it was the result of several hours of work and testing. 
    
    When you are trying to find the correct parameters, it is sensible to
    test on a partition containing lots of small files. This is the case
    when mis-tuned parameters will show up first, because the file system
    takes a lot of time for directory searches and the disk drive has to move
    heads very often, so it is most difficult for the software to keep the
    buffer full.
    
    Regards, 
    
      Peter. 

    Thank's got the TZK50 streaming with this parameters.
    
    But Ifound a problem when the Backup needs a second Tape. Everything
    seems ok. but I cant restore it. It seems that the first Index is
    unreadable. Its possible to read the last Index on the second Tape but
    there is no acces to Files on the first Tape.
    Do I have fingertroubles ?
    What are Your eperiences ?
    
    Regards
            Armin

    Hello Armin,
    
    you could get GEMAR using a second tape? In this case the TZK50 must be
    different to the TZ30 in more places than I thought. I can't even backup 
    to multiple volumes.
    
    The reason is that the TZ30 seems to go into unit attention state when
    it recognises that a tape change occurred. And it seems to provide more
    than one status information to the SCSI initiator, which is where the
    software suspects a fatal error and stops operation.
    
    Steffen already knows about the problem, but he is rather busy at the
    moment so that he has not too much time to work on it. Your error seems
    to be a different one, so you should send a bug report to him. His
    internet address is [email protected], plase don't ever send more
    than 48 kB of mail to this address.
    
    Feel free to contact me via mail if you have further questions.
    
    Regards, 
    
      Peter.

    
     I now have GEMAR v2.2, but find that the parameters noted earlier
    for the TK50Z do not seem to work so well with this new version
    (the tape now stops and restarts quite frequently).
     I plan to play with the parameters further and report here re.
    results.
    
    Best Regards,
    Brian
    

    Brian, 
    
    I forwarded your info to Steffen. I hope this is no general effect of
    the changes made to GEMAR, because otherwise *all* parameter sets have
    to be reworked ...
    
    Regards, 
    
      Peter.

    Hi Peter,
    
        I mentioned the TK50Z parameters to Steffen too (I am now a
    registered user :-) but I believe he thought that the backup buffer
    sounded to be rather on the low side, but if it worked for me with
    my configuration then O.K.  I agreed with Steffen though that perhaps
    more experimentation would be of value (although the parameters were
    arrived at after quite a long time), but I don't believe the results
    with v2.2 is a general effect of the changes made.
        Perhaps the new coding is more efficient, and a change of 1k either
    way made a significant difference before - I believe a little tweaking
    with the new version is probably all that is required. I'll update
    as soon as possible with the results for TK50Z, but I would assume that
    the parameters included in the PAR folder for other types of drives
    would probably still be O.K.?
    
    Best Regards,
    Brian
    

    
    
     After many hours of experimentation with the parameters, I find that
    with my setup (16MHz, 4MB, ICD 'Link' and ICD Pro Driver/Cache) larger
    buffer sizes cause the top bar to alternately empty and refill, and
    I have reverted back to a small buffer of only 8k. I find also that
    the 'Time Before SCSI' parameter must be selected in my setup,
    otherwise the TK50Z seems to 'hog' the SCSI bus and the disk drive
    doesn't appear to be reading frequently enough to keep the buffer
    filled up.
      The small buffer in my setup is a little confusing as I understand
    from Steffen that if the value of 'maximum read' is higher than the
    buffer size, then the buffer value is over-ridden by 'max-read'.
    It seems to work for me however, perhaps my disk-cache is contributing
    to the overall buffer.
     The parameters which work for me with the TK50Z are very similar
    to those previously, and I get good results with the following:
    
        	Backup Buffer 8KB
    		Max Read      20KB
                Data Rate     46KB
    
                Wait Before SCSI  1 tick
                Wait After  SCSI  0 tick
    
       Select X Time Before SCSI
              X Verbose
              X Immediate
              X Test Unit Ready
              X Mode Sense
              X Mode Select
              X Load/Unload Tape
    
    The 'Time Before SCSI' settings seem to keep the TK50Z and the disk
    drive both busy at the same time, and although the TK50Z paused five
    or six times during test backups of partitions containing a wide
    variety of different file sizes, the top bar does not empty.
    I think that it is possible that the tape may perhaps be pausing
    on these few occasions to do an error correction or retry - I have
    found that some cartridges do this more so than others, and the
    cartridges which I have are well used and quite old.
    
     The above works O.K. for me and was arrived at after many hours of
    experimentation, and I think that the most significant change from
    previous parameters is that the 'Time Before SCSI' figures have been
    reduced.
    
    Best Regards,
    Brian :-)
    
    
    
     

    
    I too have found the same problem as Armin reported in .13,
    when backing up files from a 330MB partition.
    I found that GEMAR asked for a new cartridge after the first and
    second were full, and although the primary index had been written
    to the first tape during the backup, and the main Index to the
    third (final) tape, GEMAR could not seem to find the index from
    either tape during a restore, so that a restore was not possible.
     I have reported this to Steffen as a possible bug, but in the
    meantime everything is O.K. with backups to a single TK50Z cartridge.
    
    Best Regards,
    Brian :-)
    

    
     I have a reply from Steffen, advising that this is not thought to be
    a bug. With backups which run to more than one cartridge, the 'last'
    cartridge, which contains the main index file, should be inserted for
    reading regarding a restore, and 'Gemar' apparantly does a 'space 
    forward' from the beginning of the cartridge until it encounters the
    main index file at the end, and then reads the index.
     I tried increasing the 'space' timeout value as advised, but this
    does not make any difference, and appears to have been large enough
    already (I think it was 1200 seconds, which should be more than
    enough).
     I think possibly it may be something to do with the large block size
    on the partition I was backing up (the drive is 330MB, and I have this
    set up as one partition, block size 8192, I think) and plan to
    experiment further in the meantime.
     Armin, what is the block size on the partition you backed up?
    
    Best Regards,
    Brian
    

    
     I found out during the weekend that the 'block-size' in -1. has
    nothing to do with the problem - silly me :-)
    
     It seems that the TK50Z takes 30 minutes to find the index file
    written at the end of a three-cartridge set , so the Space-Timeout
    value needs to be somewhere around 2400s (40 minutes).
     I had tried this value earlier, but had aborted after 25 minutes -
    if I had waited another 5 minutes, I would have seen that the index
    was read O.K. 
     I don't know why the TK50Z takes so long to find and read the index
    in this situation (the backups was from a 330MB partition, with
    536 folders containing 3932 files in 253MB) but I found that file
    restores were O.K.
     I find that Image backups are much quicker, although I have not
    yet tried an Image restore.
     I also find that the TK50Z finds and reads the Index file on a
    single cartridge backup relatively quickly.
    
    Best Regards,
    Brian
    

    
    re. -18
    
    Brian, the drive has to stop once in a while to switch to reverse
    direction when it reached the end of one track. The TK50Z does
    Serpentine Recording with only one track, so this is normal even
    when the buffer display shows full.
    
    Bernd
    
    P.S. sorry for not receiving any replies to your internet-mails to my
    home account. The MausNet encountered a problem with personal mails
    after they installed version "d" of the software ;-(
    Receiving is ok, but no PM leaves the gateway...
    
    

    
    re. -1,
    
    	Thanks Bernd, I hadn't thought of that :-)
    
    Brian
    

    
      I borrowed a TZ30 over the weekend to see how it would perform
    compared to the TK50Z, and while the TK50Z has been giving good
    results on my Falcon, I found I couldn't get the TZ30 to work
    very well at all.
      With Gemar v2.20, I found that the drive was seen O.K. but
    the 'load tape' command would bring up a 'command timeout' alert,
    and hang the machine if I tried it again. Deselecting 'mode select'
    and 'mode sense' in the streamer parameter dialogue box and selecting
    only 'test unit ready' enabled the tape to respond to the 'load tape'
    command, but on commencing a write to tape following reading of the
    drive index file, an error 'error writing TAR header' and 'incorrect
    SCSI command' appeared, with an alert box requesting an 'abort' action.
      I am wondering if perhaps the TZ30 is broken (the TK50Z works O.K.)
    I would be interested in hearing if anyone else has seen this, and if
    there are any specific switch/jumper settings on the TZ30 which should
    be taken into account.
    
    Thanks and Best Regards,
    Brian
    

    
       I found that the TZ30 works O.K. with my STFM, so perhaps there
    is a problem with the Falcon/TZ30 combination.
    
    Best Regards,
    Brian
    

Well I finally got a chance to play with a tape drive and GEMAR. WOW! What a
big difference over backing up to floppies!

I did run into a few glitches though, and was wondering if anyone else has
seen these problems and/or knows how to fix them? All these comments are based
on using GEMAR V2.20 available on the net.

When writing the index at the end of a backup, GEMAR access's the floppy drive
(drive A:). Does anyone know why it access drive A:? It doesn't create any
(visible) files on the floppy, just lights the light and you can hear the head
move.

When GEMAR does a restore it creates the files on the hard drive with the
CURRENT date and NOT the original date of the backed up files. It does store
the correct date on the tape, it just doesn't use that date when doing a
restore. I looked all over trying to find a menu option to change this
behavior, with no success.

Another restore problem is that it doesn't correctly handle folder names with
embedded colons. ie: When restoring a folder name of /TOOLS/A:CALC/, GEMAR
created /TOOLS on the hard drive and then created /CALC on the floppy drive A:.
Of course it got an error when it tried to restore the first file to
/TOOLS/A:CALC/ as the folder was non existent.

Does anyone know the difference between using the RESTORE item in the main
menu and the RESTORE item in the window menu? One of the readme files
indicates there is a difference but refers you to the manual (which has not
been translated to English) to find out the difference.

GEMAR was not able to read a tar tape created on Ultrix. I think when I asked
for an index it just came up empty, I can't remember for sure. I'm still
looking at this problem. Perhaps its a problem with compression enabled on one
machine and not the other. Ultrix tar WAS able to read a GEMAR created tape,
it created a folder for the drive letter and all of the files were in
uppercase, but other than that it worked great.

  Thanks,

	Ray

    Hello Ray, 
    
    Maybe I can shed some light on some of your points. Anyway, I forwarded
    your mail to Steffen Engel for the rest of your questions.
    
    > When writing the index at the end of a backup, GEMAR access's the
    > floppy drive (drive A:). Does anyone know why it access drive A:? 
    
    I also use the 2.20 version, and I never had this effect. So probably
    there is either a bug or you misconfigured something. Did you start
    GEMAR from floppy? It writes a log file and a directory of indices
    after finishing backups, the latter is in order to recognize if the
    first index is correct without reading the second index at the end of
    the tape. If you started from floppy, it will create the files there.
    
    > Another restore problem is that it doesn't correctly handle folder
    > names with embedded colons. ie: When restoring a folder name of 
    > /TOOLS/A:CALC/, GEMAR created /TOOLS on the hard drive and then created 
    > /CALC on the floppy drive A:.
    
    How did you create that folder? Folder names with colons are not
    supported by TOS or MagiC!, so I'm not very surprised that a TOS
    program can't handle them properly.
    
    > Does anyone know the difference between using the RESTORE item in 
    > the main menu and the RESTORE item in the window menu? One of the 
    > readme files indicates there is a difference but refers you to the 
    > manual (which has not been translated to English) to find out the 
    > difference.
    
    I don't have the manual here at the moment, but I will take a look and
    tell you if I don't forget.
    
    GEMAR was not able to read a tar tape created on Ultrix. [...] Ultrix
    tar WAS able to read a GEMAR created tape, [...]
    
    That's the way it's supposed to work. 
    
    After version 2.12, GEMAR has dropped support for reading TAR tapes and
    just writes TAR compatible headers. Steffen told me that TAR support
    was too complicated to maintain within GEMAR, because there is a large
    variety of TAR formats around (Unix, sigh). If you are using
    MinT/MultiTOS, it is possible to obtain a TAR file system extension,
    since I don't, I do not know exactly where to find it and how it works.
    
    Regards, 
    
      Peter.
    

    
    Hello Ray, Peter,
    
     I also took the opportunity to put Ray's questions to the
    author - I hope I am not overstepping any response Peter has
    planned, but if I may, here is Steffens reply. I have been off-line
    for a while due to a serious fault in my telephone line, and while
    the reply was received just before my phone line went down, I am
    only now in a position to post it, with apologies for any delay...
    
    BR>behalf of a friend at work
    That's ok, I'll do my very best.
    
    BR>GEMAR access's the floppy drive (drive A:).
    Hm, never heard of, never seen. Maybe there is 'A:' in the PATH-
    Environment. When finishing the Backup, GEMAR searches for an existing
    GEMAR.KEY and GEMAR.LOG with shel_find. If they do not exist, they are
    created in GEMAR's home directory.
    Due to the shel_find-operation of the AES all Paths given in PATH are
    searched for these files, so maybe there is A: in PATH.
    
    BR>When GEMAR does a restore it creates the files on the hard drive
    with
    BR>the CURRENT date and NOT the original date of the backed up files.
    Very strange, because on my system the date is set to the original
    date.
    Maybe there is any AUTO-program changing the behaviour of the GEMDOS
    call
    Fdatime.
    You can check for the existance of the call with SYSMON.
    Which version of TOS do you use?
    
    BR>Another restore problem is that it doesn't correctly handle folder
    BR>names with embedded colons.
    A colon is a forbidden character in file names, so this is no bug, it's
    a
    feature.
    
    BR>Does anyone know the difference between using the RESTORE item in
    the
    BR>main menu and the RESTORE item in the window menu?
    I call it local and global restore. If you use the local restore (in
    the
    window menu), only those files are restored, which are in the open
    window
    and deeper.
    
    For example:
    
    in a backup there is the folder C:\TEST1\ with the files FILE1 FILE2
    ...
    FILE10 and a folder C:\TEST2\ with the files FILE11 ... FILE20
    Open the path for C:\ and select all. Then open the folder TEST1 and do
    a global and local restore with the destination path to C:\CLIPBRD\
    
    The global restore will give:
    
    C:\CLIPBRD\
     TEST1\
       FILE1
       FILE2
       ...
       FILE10
     TEST2\
       FILE11
       ...
       FILE20
    
    The local restore will give
    
     C:\CLIPBRD\
       FILE1
       ...
       FILE10
    
    because the opened window is C:\TEST1\
    
    BR>GEMAR was not able to read a tar tape created on Ultrix.
    GEMAR can' read a TAR index it only write TAR compatible archives.. For
    reading TAR-archives you must use the devicedriver under MiNT and a
    normal TAR.TTP
    
    
    Best Regards,
    Brian
    
    

Thanks a lot for getting this feedback from the author.

The difference between the two restores sounds real usefull.

I'll take a look at my path and my auto folder to see if I can find the cause
of the floppy access and the date problem.

Atari docs do state that using a colon in a file or directory name is illegal,
however TOS and the desktop (TOS 1.2) allow the creation of directories with
an embeded colon and since the name of program is A:CALC the vendor (it's a
commercial spreadsheet) decided to put the program and its files in a
directory of the same name. It's simple enough to change the directory name,
so no real problem. Note that GEMAR is the only program I've run across which
has a problem with this.
    
I've got a couple of other ST tar programs that I'm going to try out,
hopefully one of them will be able to read the Ultrix tar tapes. It would be
much nicer than using floppies to move large amounts of files back and forth.

  Thanks,

	Ray

    
    Ray, I can't believe that in TOS version 1.2 you can use semicolons and
    colons in a file- or directory name. This would be against all rules of
    the 8.3-structure (which is still a heritage from C/PM and DOS). I
    don't have 1.2 anymore, but 2.06 and MagiC definitely don't allow this.
    Hm, this is really very interesting.Could it be that there are
    differences in the country versions of TOS (e.g. GY vs. UK)?
    
    Bernd