US Robotics 7931 Podręcznik Użytkownika Pobierz pdf (Strona 66)

42 Sun StorageTek SAM Archive Configuration and Administration Guide • Version 4, Update 6, 04/07

threshold above which additional volumes or media are assigned for archiving. An

ovflmin value specified for the archive set takes precedence over an ovflmin value

specified for the media.

If the size of the files is less than the value of ovflmin, the files cannot be archived.

An appropriate message for this condition is sent to the log. If the size of the files is

more than the value of ovflmin, additional volumes are assigned as required.

Volumes are selected in order of decreasing size in order to minimize the number of

volumes required. If no usable volumes can be found for the archive request, the

archive request waits until volumes become available.

Certain properties, such as whether the file is online or offline, are used in

conjunction with the archive priority to determine the scheduling priority for a

particular archive request. For more information on customizing the priority

multiplier, see the -priority parameters described on the archiver.cmd(4) man

page.

For each archive request, the sam-archiverd daemon computes the scheduling

priority by adding the archive priority to multipliers associated with various system

resource properties. These properties are associated with the number of seconds for

which the archive request has been queued, whether the first volume to be used in

the archiving process is loaded into a drive, and so on.

Using the adjusted priorities, the sam-archiverd daemon assigns each ready

archive request to be copied, as described in the next section.

Step 4: Archiving the Files in an Archive Request

When an archive request is ready to be archived, the sam-archiverd daemon

marks the archive file (tarball) boundaries so that each archive file’s size is less than

the specified -archmax value. If a single file is larger than this value, it becomes the

only file in an archive file.

For each archive request and each drive to be used, the sam-archiverd daemon

assigns the archive request to a sam-arcopy process to copy the files to the archive

media. The archive information is entered into the inode.

If archive logging is enabled, an archive log entry is created.

For each file that was staged, the disk space is released until all files in the list have

been archived.

A variety of errors and file status changes can prevent a file from being successfully

copied. Errors can include read errors from the cache disk and write errors to the

volumes. Status changes can include modification since selection, a file that is open

for writing, or a file that has been removed.

1 2 ... 61 62 63 64 65 66 67 68 69 70 71 ... 287 288

Brak uwag

US Robotics 7931 Podręcznik Użytkownika Strona 66