1 /* 2 drbd_limits.h 3 This file is part of DRBD by Philipp Reisner and Lars Ellenberg. 4 */ 5 6 /* 7 * Our current limitations. 8 * Some of them are hard limits, 9 * some of them are arbitrary range limits, that make it easier to provide 10 * feedback about nonsense settings for certain configurable values. 11 */ 12 13 #ifndef DRBD_LIMITS_H 14 #define DRBD_LIMITS_H 1 15 16 #define DEBUG_RANGE_CHECK 0 17 18 #define DRBD_MINOR_COUNT_MIN 1 19 #define DRBD_MINOR_COUNT_MAX 256 20 #define DRBD_MINOR_COUNT_DEF 32 21 22 #define DRBD_VOLUME_MAX 65535 23 24 #define DRBD_DIALOG_REFRESH_MIN 0 25 #define DRBD_DIALOG_REFRESH_MAX 600 26 27 /* valid port number */ 28 #define DRBD_PORT_MIN 1 29 #define DRBD_PORT_MAX 0xffff 30 31 /* startup { */ 32 /* if you want more than 3.4 days, disable */ 33 #define DRBD_WFC_TIMEOUT_MIN 0 34 #define DRBD_WFC_TIMEOUT_MAX 300000 35 #define DRBD_WFC_TIMEOUT_DEF 0 36 37 #define DRBD_DEGR_WFC_TIMEOUT_MIN 0 38 #define DRBD_DEGR_WFC_TIMEOUT_MAX 300000 39 #define DRBD_DEGR_WFC_TIMEOUT_DEF 0 40 41 #define DRBD_OUTDATED_WFC_TIMEOUT_MIN 0 42 #define DRBD_OUTDATED_WFC_TIMEOUT_MAX 300000 43 #define DRBD_OUTDATED_WFC_TIMEOUT_DEF 0 44 /* }*/ 45 46 /* net { */ 47 /* timeout, unit centi seconds 48 * more than one minute timeout is not useful */ 49 #define DRBD_TIMEOUT_MIN 1 50 #define DRBD_TIMEOUT_MAX 600 51 #define DRBD_TIMEOUT_DEF 60 /* 6 seconds */ 52 53 /* If backing disk takes longer than disk_timeout, mark the disk as failed */ 54 #define DRBD_DISK_TIMEOUT_MIN 0 /* 0 = disabled */ 55 #define DRBD_DISK_TIMEOUT_MAX 6000 /* 10 Minutes */ 56 #define DRBD_DISK_TIMEOUT_DEF 0 /* disabled */ 57 #define DRBD_DISK_TIMEOUT_SCALE '1' 58 59 /* active connection retries when C_WF_CONNECTION */ 60 #define DRBD_CONNECT_INT_MIN 1 61 #define DRBD_CONNECT_INT_MAX 120 62 #define DRBD_CONNECT_INT_DEF 10 /* seconds */ 63 64 /* keep-alive probes when idle */ 65 #define DRBD_PING_INT_MIN 1 66 #define DRBD_PING_INT_MAX 120 67 #define DRBD_PING_INT_DEF 10 68 69 /* timeout for the ping packets.*/ 70 #define DRBD_PING_TIMEO_MIN 1 71 #define DRBD_PING_TIMEO_MAX 300 72 #define DRBD_PING_TIMEO_DEF 5 73 74 /* max number of write requests between write barriers */ 75 #define DRBD_MAX_EPOCH_SIZE_MIN 1 76 #define DRBD_MAX_EPOCH_SIZE_MAX 20000 77 #define DRBD_MAX_EPOCH_SIZE_DEF 2048 78 79 /* I don't think that a tcp send buffer of more than 10M is useful */ 80 #define DRBD_SNDBUF_SIZE_MIN 0 81 #define DRBD_SNDBUF_SIZE_MAX (10<<20) 82 #define DRBD_SNDBUF_SIZE_DEF 0 83 84 #define DRBD_RCVBUF_SIZE_MIN 0 85 #define DRBD_RCVBUF_SIZE_MAX (10<<20) 86 #define DRBD_RCVBUF_SIZE_DEF 0 87 88 /* @4k PageSize -> 128kB - 512MB */ 89 #define DRBD_MAX_BUFFERS_MIN 32 90 #define DRBD_MAX_BUFFERS_MAX 131072 91 #define DRBD_MAX_BUFFERS_DEF 2048 92 93 /* @4k PageSize -> 4kB - 512MB */ 94 #define DRBD_UNPLUG_WATERMARK_MIN 1 95 #define DRBD_UNPLUG_WATERMARK_MAX 131072 96 #define DRBD_UNPLUG_WATERMARK_DEF (DRBD_MAX_BUFFERS_DEF/16) 97 98 /* 0 is disabled. 99 * 200 should be more than enough even for very short timeouts */ 100 #define DRBD_KO_COUNT_MIN 0 101 #define DRBD_KO_COUNT_MAX 200 102 #define DRBD_KO_COUNT_DEF 0 103 /* } */ 104 105 /* syncer { */ 106 /* FIXME allow rate to be zero? */ 107 #define DRBD_RESYNC_RATE_MIN 1 108 /* channel bonding 10 GbE, or other hardware */ 109 #define DRBD_RESYNC_RATE_MAX (4 << 20) 110 #define DRBD_RESYNC_RATE_DEF 250 111 #define DRBD_RESYNC_RATE_SCALE 'k' /* kilobytes */ 112 113 /* less than 7 would hit performance unnecessarily. 114 * 919 slots context information per transaction, 115 * 32k activity log, 4k transaction size, 116 * one transaction in flight: 117 * 919 * 7 = 6433 */ 118 #define DRBD_AL_EXTENTS_MIN 7 119 #define DRBD_AL_EXTENTS_MAX 6433 120 #define DRBD_AL_EXTENTS_DEF 127 121 122 #define DRBD_MINOR_NUMBER_MIN -1 123 #define DRBD_MINOR_NUMBER_MAX (1<<30) 124 #define DRBD_MINOR_NUMBER_DEF -1 125 #define DRBD_MINOR_NUMBER_SCALE '1' 126 127 /* } */ 128 129 /* drbdsetup XY resize -d Z 130 * you are free to reduce the device size to nothing, if you want to. 131 * the upper limit with 64bit kernel, enough ram and flexible meta data 132 * is 1 PiB, currently. */ 133 /* DRBD_MAX_SECTORS */ 134 #define DRBD_DISK_SIZE_MIN 0 135 #define DRBD_DISK_SIZE_MAX (1 * (2LLU << 40)) 136 #define DRBD_DISK_SIZE_DEF 0 /* = disabled = no user size... */ 137 #define DRBD_DISK_SIZE_SCALE 's' /* sectors */ 138 139 #define DRBD_ON_IO_ERROR_DEF EP_DETACH 140 #define DRBD_FENCING_DEF FP_DONT_CARE 141 #define DRBD_AFTER_SB_0P_DEF ASB_DISCONNECT 142 #define DRBD_AFTER_SB_1P_DEF ASB_DISCONNECT 143 #define DRBD_AFTER_SB_2P_DEF ASB_DISCONNECT 144 #define DRBD_RR_CONFLICT_DEF ASB_DISCONNECT 145 #define DRBD_ON_NO_DATA_DEF OND_IO_ERROR 146 #define DRBD_ON_CONGESTION_DEF OC_BLOCK 147 148 #define DRBD_MAX_BIO_BVECS_MIN 0 149 #define DRBD_MAX_BIO_BVECS_MAX 128 150 #define DRBD_MAX_BIO_BVECS_DEF 0 151 152 #define DRBD_C_PLAN_AHEAD_MIN 0 153 #define DRBD_C_PLAN_AHEAD_MAX 300 154 #define DRBD_C_PLAN_AHEAD_DEF 0 /* RS rate controller disabled by default */ 155 156 #define DRBD_C_DELAY_TARGET_MIN 1 157 #define DRBD_C_DELAY_TARGET_MAX 100 158 #define DRBD_C_DELAY_TARGET_DEF 10 159 160 #define DRBD_C_FILL_TARGET_MIN 0 161 #define DRBD_C_FILL_TARGET_MAX (1<<20) /* 500MByte in sec */ 162 #define DRBD_C_FILL_TARGET_DEF 0 /* By default disabled -> controlled by delay_target */ 163 164 #define DRBD_C_MAX_RATE_MIN 250 /* kByte/sec */ 165 #define DRBD_C_MAX_RATE_MAX (4 << 20) 166 #define DRBD_C_MAX_RATE_DEF 102400 167 168 #define DRBD_C_MIN_RATE_MIN 0 /* kByte/sec */ 169 #define DRBD_C_MIN_RATE_MAX (4 << 20) 170 #define DRBD_C_MIN_RATE_DEF 4096 171 172 #define DRBD_CONG_FILL_MIN 0 173 #define DRBD_CONG_FILL_MAX (10<<21) /* 10GByte in sectors */ 174 #define DRBD_CONG_FILL_DEF 0 175 176 #define DRBD_CONG_EXTENTS_MIN DRBD_AL_EXTENTS_MIN 177 #define DRBD_CONG_EXTENTS_MAX DRBD_AL_EXTENTS_MAX 178 #define DRBD_CONG_EXTENTS_DEF DRBD_AL_EXTENTS_DEF 179 180 #define DRBD_PROTOCOL_DEF DRBD_PROT_C 181 182 #define DRBD_DISK_BARRIER_DEF 0 183 #define DRBD_DISK_FLUSHES_DEF 1 184 #define DRBD_DISK_DRAIN_DEF 1 185 #define DRBD_MD_FLUSHES_DEF 1 186 #define DRBD_TCP_CORK_DEF 1 187 188 #define DRBD_ALLOW_TWO_PRIMARIES_DEF 0 189 #define DRBD_ALWAYS_ASBP_DEF 0 190 #define DRBD_USE_RLE_DEF 0 191 192 #endif 193