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..22-Dec-201614

autogen.shH A D08-Mar-2015123

ChangeLogH A D08-Mar-20153.8 KiB

changelog_from_git.shH A D08-Mar-201571

config/H20-Dec-20163

configure.inH A D08-Mar-20151.6 KiB

COPYINGH A D08-Mar-20151.6 KiB

libsdp.confH A D08-Mar-20155.6 KiB

libsdp.spec.inH A D08-Mar-20151.3 KiB

Makefile.amH A D08-Mar-2015721

NEWSH A D08-Mar-2015158

READMEH A D08-Mar-20153.3 KiB

src/H20-Dec-201612

README

1LIBSDP - A User Level Socket Switch for Seemless Migration to SDP 
2-----------------------------------------------------------------
3
4OVERVIEW:
5---------
6libsdp is a LD_PRELOAD-able library that can be used to migrate existing
7applications use InfiniBand Sockets Direct Protocol (SDP) instead of
8TCP sockets, transparently and without recompilations. To setup libsdp
9please follow the instructions below.
10
11SETUP:
12------
13libsdp.so isn't setup automatically. it can be used in one of 2 ways:
141) LD_PRELOAD environment variable. Setting this to the name of the
15   library you want to use will cause it to be preloaded.
162) Adding the name of the library into /etc/ld.so.preload. This will
17   cause the library to be preloaded for every executable that is linked
18   with libc.
19
20The library should be installed in a directory in which the dynamic loader
21searches for shared libraries (as specified by LD_LIBRARY_PATH,
22/etc/ld.so.conf, etc). Alternatively, you can specify the full path to the 
23library that you want to use in LD_PRELOAD or /etc/ld.so.preload as described 
24above.
25
26The last option cant be used if you have multiple library versions
27(e.g. 64/32 bit) and want the linker to select between them automatically.
28The best way to handle such case is to use LD_LIBRARY_PATH to point to both the
29lib (the 32 bit version) and lib64 directories and LD_RELOAD the libsdp.so.
30This way the correct 32/64bit libsdp.so will be selected. 
31For example running ssh over SDP with OFED distribution from bash this can be written:
32LD_LIBRARY_PATH=/usr/local/ofed/lib64:/usr/local/ofed/lib LD_PRELOAD=libsdp.so ssh
33
34CONFIGURATION:
35--------------
36libsdp supports two modes of configuration:
37* simple operation where it converts all calls to socket(2) with a family
38  of AF_INET(6) and a type of SOCK_STREAM into family of AF_INET_SDP. 
39* selective mode where it uses a configuration file to select which sockets
40  will be using SDP and which will not.
41
42For real world applications where communication with X, authentication, 
43DNS and other servers connected through TCP is required the selective mode
44is required.
45
46Simple mode will be selected in one of the following conditions:
47* the environment variable SIMPLE_LIBSDP to a non-empty value
48* no configuration file is defined or is un-readble
49* the configuration file does not include any address family rule
50
51For information on how to configure libsdp, see libsdp.conf, which is installed
52in $(sysconfdir) (usually /usr/local/etc or /etc). The user can further control
53the file to be used for configuration by setting the environment variable:
54LIBSDP_CONFIG_FILE
55
56LIMITATIONS:
57------------
581. Applications statically linked with libc will not allow dynamic pre-loading
59   to port these applications to use SDP one needs to replace specific socket 
60   calls (within the application) with AF_INET_SDP and recompile.
612. If for some reason the dynamic linker fail to pre-load libc before the 
62   libsdp.so is initialized or it does not support RTDL_NEXT, libsdp will 
63   fail to find the libc socket API. To overcome this situation a simple 
64   implementation of hijacking "socket" call is provided in libsdp_sys.
65   This partial implementation does not support any configuration and is 
66   limited to i386 architecture.
673. Non-blocking connect in "both" mode defaults to SDP. Specific rules might be
68   needed for applications to operate properly.
69