#pragma once #define NPROC 128 // maximum number of processes #define KSTACKSIZE 4096 // size of per-process kernel stack (increased for x64) #define KSTACK_CANARY 0xDEADC0DEDEADC0DEULL // sentinel at kstack[0], see kstack_check_canary() #define NCPU 16 // maximum number of CPUs #define NOFILE 128 // open files per process #define NFILE 512 // open files per system #define NINODE 200 // maximum number of active i-nodes #define NDEV 10 // maximum major device number #define RAMDISK_DEV 2 // memory-backed block device (kernel/dev/ramdisk.c) #define USBDISK_DEV 3 // USB mass storage (kernel/drivers/usb_storage.c) // Device the root filesystem is mounted from. Building with RAMROOT=1 defines // RAMDISK_ROOT and boots from the SCHFS image linked into the kernel instead // of the IDE disk, leaving the physical disk free to be reformatted from a // running system. See kernel/dev/ramdisk.c. #ifdef RAMDISK_ROOT #define ROOTDEV RAMDISK_DEV #else #define ROOTDEV 1 // device number of file system root disk #endif #define MAXARG 32 // max exec arguments #define MAXPATH 128 // max path #define MAXOPBLOCKS 30 // max # of blocks any FS op writes #define LOGSIZE (MAXOPBLOCKS*3) // max data blocks in on-disk log // Disk block cache, in blocks. 256 * BSIZE = 1 MB. // // Was MAXOPBLOCKS*3 = 90 blocks, and at the old 1 KB BSIZE that is a 90 KB // cache -- smaller than the toybox binary that every single command execs. So // nothing was ever still resident on the next command and each one paid the // full read again. 1 MB holds toybox with room to spare, which is what makes // the *second* command fast rather than just the first. // // Sized rather than maximised: these are statically allocated in bio.c, so // this is memory the system always spends. 1 MB is affordable on a machine // with tens of megabytes; 8 MB would not be. #define NBUF 256 #define FSSIZE 150000 // size of file system in blocks // Network interfaces the stack will attach. Two is already an ordinary machine // -- a laptop with Ethernet plus a virtual adapter -- and each one costs a // struct netif, so the limit is about keeping a fixed array honest rather than // about memory. #define NETIF_MAX 4