6-Sep-2005

Hi everyone,

We've made two changes to the way the RHESSI software finds data files.  These
changes should be transparent to most users.

SUMMARY:

The first change is optional.  If your HSI_DATA_ARCHIVE points to a full RHESSI
data archive, add this line to your site-specific setup.hessi_env file (usually
in $SSW/site/setup or $HOME on UNIX) to prevent the possibility of searching for
a file throughout the entire archive (which can take >30 minutes):

setenv HSI_ARCHIVE_MOUNTED   true

The second change will affect you only if you are not connected to a full RHESSI
data archive, and have been manually putting data files in directories other
than HSI_DATA_USER or HSI_DATA_ARCHIVE.  If so, you should move the files to
HSI_DATA_USER.  The change is that the search path for data files is reduced to
the following directories:

Current Directory
HSI_DATA_ARCHIVE (expanded)
HSI_DATA_USER (expanded)

(You'll get these software changes in your next SSW udpate after 10am EDT
Tuesday, Sept 6.)


If you want to know the details, keep reading.

-------     1.)  HSI_ARCHIVE_MOUNTED environment variable added

The first change is optional and only applies to users who are connected to the
full RHESSI data archive (via NFS mount, Samba share, or equivalent).

The software looks for a data file in the archive in its expected directory
(year/month/day of data).  On rare occasions the file may not be found (maybe
because of an out-of-sync filedb file) and then it searches the entire archive.
The archive is huge (it currently contains >18,000 directories and takes >15
minutes just to build the list of directories to search!) and this search can
take a really long time.

We've added an environment variable that you can set to prevent the software
from ever searching the entire RHESSI data archive.  HSI_ARCHIVE_MOUNTED was
added to $SSW/hessi/setup/setup.hessi_env.  Its default value is 'false'.  If
your HSI_DATA_ARCHIVE points to the full RHESSI data archive you should add the
following line to your site-specific setup.hessi_env file (usually in
$SSW/site/setup or your $HOME directory on UNIX):
setenv HSI_ARCHIVE_MOUNTED   true
With this set, and if the HSI_DATA_ARCHIVE directory is visible, the software
will only look in the expected directory for the file, and never search the
entire archive (or HSI_DATA_USER or across the network).

This is optional.  It will continue to work as before if you don't make this
change.

Laptop users:  The HSI_ARCHIVE_MOUNTED feature only has an effect if the
directory pointed to by HSI_DATA_ARCHIVE is reachable.  So if you set
HSI_DATA_ARCHIVE to the full RHESSI data archive and HSI_ARCHIVE_MOUNTED to
'true' on a laptop, then when the laptop is not connected to the archive, the
software will proceed as before to search the HSI_DATA_USER directory, and to
search across the network (if you've enabled search_network),  i.e. you don't
need to change the settings.

-------     2.)  HESSI_DATA_PATHS streamlined

The second change applies only to users who are not connected to the full RHESSI
data archive.  The list of directories to search for data files has been
shortened.  If you have been manually putting data files in your HSI_DATA_USER
location (which is also where the search_network automatic copying feature puts
files), then this change will not affect you.

Previously hessi_data_paths() constructed a long list of directories to search
including these environment variables: SSW_HESSI, HSI_DATA_ARCHIVE,
HSI_DATA_USER, SSWDB_HESSI, HESSI_DBASE, HSI_USER_DATA, SPEX_USER_DATA as
well
as all RHESSI environment variables in the setup.hessi_env file.  Now the list
is shortened to include only the current directory, HSI_DATA_ARCHIVE and its
subdirectories (if HSI_ARCHIVE_MOUNTED is false), and HSI_DATA_USER and its
subdirectories.  If you were manually putting files in some of the other
directories hessi_data_paths previously used, you'll need to copy them to
HSI_DATA_USER.

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There's more information about  finding data files and setting environment
variables in the RHESSI FAQ.

Kim Tolbert