explication of forcedirectio Post: 302388516

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Operating Systems Solaris explication of forcedirectio Post 302388516 by DukeNuke2 on Wednesday 20th of January 2010 05:07:03 PM

01-20-2010

Registered User

Quote:

"forcedirectio" option is useful for large files. From the mount_ufs man page, we see this explanation:

"If forcedirectio is specified and supported by the file system, then for the duration of the mount forced direct I/O will be used. If the filesystem is mounted using forcedirectio, then data is transferred directly between user address space and the disk. If the filesystem is mounted using noforcedirectio, then data is buffered in kernel address space when data is transferred between user address space and the disk. forcedirectio is a performance option that benefits only from large sequential data transfers. The default behavior is noforcedirectio."

btw. this was the first google hit for "solaris mount forcedirectio"!

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install-solaris

install-solaris(1M)													       install-solaris(1M)

NAME

       install-solaris - install the Solaris operating system

SYNOPSIS

       install-solaris

       install-solaris	invokes  the  Solaris  Install	program. Depending on graphical capability and available memory at the time of invocation,
       install-solaris invokes either a text-based installer or a graphical installer.

       The following minimum requirements for physical memory dictate which features are available during installation:

       For SPARC machines:

       128 MB

	   Minimum physical memory for all installation types

       128 MB

	   Minimum physical memory required for windowing system

       384 MB

	   Minimum physical memory required for graphical-based installation

       For x86 machines:

       256 MB

	   Minimum physical memory for all installation types

       256 MB

	   Minimum physical memory required for windowing system

       512 MB

	   Minimum physical memory required for graphical-based installation

       In some cases, even if the minimum physical memory is present, available virtual memory after system startup can limit the number  of  fea-
       tures available.

       install-solaris	exists	only  on  the Solaris installation media (CD or DVD) and should be invoked only from there. Refer to the  for more
       details.

       install-solaris allows installation of the operating system onto any standalone system. install-solaris loads the software available on the
       installation media. Refer to the  for disk space requirements.

       Refer to the  for more information on the various menus and selections.

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcdrom  (Solaris instal-  |
       |			     |lation media)		   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

       pkginfo(1), install(1M), pkgadd(1M), attributes(5)

       It is advisable to exit install-solaris by means of the exit options in the install-solaris menus.

								    23 Sep 2005 					       install-solaris(1M)