Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 1 | /* |
| 2 | include/types/backend.h |
| 3 | This file rassembles definitions for backends |
| 4 | |
Willy Tarreau | 1a20a5d | 2007-11-01 21:08:19 +0100 | [diff] [blame] | 5 | Copyright (C) 2000-2007 Willy Tarreau - w@1wt.eu |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 6 | |
| 7 | This library is free software; you can redistribute it and/or |
| 8 | modify it under the terms of the GNU Lesser General Public |
| 9 | License as published by the Free Software Foundation, version 2.1 |
| 10 | exclusively. |
| 11 | |
| 12 | This library is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | Lesser General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU Lesser General Public |
| 18 | License along with this library; if not, write to the Free Software |
| 19 | Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef _TYPES_BACKEND_H |
| 23 | #define _TYPES_BACKEND_H |
| 24 | |
Willy Tarreau | e3ba5f0 | 2006-06-29 18:54:54 +0200 | [diff] [blame] | 25 | #include <common/config.h> |
| 26 | |
Willy Tarreau | df36614 | 2007-11-30 16:23:20 +0100 | [diff] [blame] | 27 | /* Parameters for proxy->lbprm.algo. |
| 28 | * The low part of the value is unique for each algo so that applying the mask |
| 29 | * BE_LB_ALGO returns a unique algorithm. |
| 30 | * The high part indicates specific properties. |
| 31 | */ |
| 32 | |
| 33 | /* Masks to extract algorithm properties */ |
| 34 | #define BE_LB_ALGO 0x000007FF /* mask to extract all algorithm flags */ |
| 35 | #define BE_LB_PROP_DYN 0x00000100 /* mask to match dynamic algorithms */ |
| 36 | #define BE_LB_PROP_L4 0x00000200 /* mask to match layer4-based algorithms */ |
| 37 | #define BE_LB_PROP_L7 0x00000400 /* mask to match layer7-based algorithms */ |
| 38 | |
| 39 | /* the algorithms themselves */ |
| 40 | #define BE_LB_ALGO_NONE 0x00000000 /* dispatch or transparent mode */ |
| 41 | #define BE_LB_ALGO_RR (BE_LB_PROP_DYN | 0x01) /* fast weighted round-robin mode (dynamic) */ |
| 42 | #define BE_LB_ALGO_SH (BE_LB_PROP_L4 | 0x02) /* balance on source IP hash */ |
| 43 | #define BE_LB_ALGO_UH (BE_LB_PROP_L7 | 0x03) /* balance on URI hash */ |
| 44 | #define BE_LB_ALGO_PH (BE_LB_PROP_L7 | 0x04) /* balance on URL parameter hash */ |
Willy Tarreau | b625a08 | 2007-11-26 01:15:43 +0100 | [diff] [blame] | 45 | |
| 46 | /* various constants */ |
Willy Tarreau | b698f0f | 2007-12-02 11:01:23 +0100 | [diff] [blame] | 47 | |
| 48 | /* The scale factor between user weight an effective weight allows smooth |
| 49 | * weight modulation even with small weights (eg: 1). It should not be too high |
| 50 | * though because it limits the number of servers in FWRR mode in order to |
| 51 | * prevent any integer overflow. The max number of servers per backend is |
| 52 | * limited to about 2^32/255^2/scale ~= 66051/scale. A scale of 16 looks like |
| 53 | * a good value, as it allows more than 4000 servers per backend while leaving |
| 54 | * modulation steps of about 6% for servers with the lowest weight (1). |
| 55 | */ |
| 56 | #define BE_WEIGHT_SCALE 16 |
Willy Tarreau | b625a08 | 2007-11-26 01:15:43 +0100 | [diff] [blame] | 57 | |
Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame] | 58 | #endif /* _TYPES_BACKEND_H */ |
| 59 | |
| 60 | /* |
| 61 | * Local variables: |
| 62 | * c-indent-level: 8 |
| 63 | * c-basic-offset: 8 |
| 64 | * End: |
| 65 | */ |