Determine values of several system variables in the terminal in a Mac

Question

I'm on a Mac. In the terminal, how would you figure out each of the following values?

• Word size (64 bit vs. 32 bit)
• L1/L2 cache size
• Determine how much memory is being used (like df, but for RAM)

Thanks! I know you can find these in Activity Monitor, System Profiler etc. but I am trying to boost my knowledge of the terminal, and UNIX.

Answer 1

System Profiler is a GUI wrapper around /usr/sbin/system_profiler.

mress:10008 Z$ system_profiler -listDataTypes 
Available Datatypes:
SPHardwareDataType
SPNetworkDataType
SPSoftwareDataType
SPParallelATADataType
SPAudioDataType
SPBluetoothDataType
SPCardReaderDataType
SPDiagnosticsDataType
SPDiscBurningDataType
SPEthernetDataType
SPFibreChannelDataType
SPFireWireDataType
SPDisplaysDataType
SPHardwareRAIDDataType
SPMemoryDataType
SPPCIDataType
SPParallelSCSIDataType
SPPowerDataType
SPPrintersDataType
SPSASDataType
SPSerialATADataType
SPUSBDataType
SPAirPortDataType
SPFirewallDataType
SPNetworkLocationDataType
SPModemDataType
SPNetworkVolumeDataType
SPWWANDataType
SPApplicationsDataType
SPDeveloperToolsDataType
SPExtensionsDataType
SPFontsDataType
SPFrameworksDataType
SPLogsDataType
SPManagedClientDataType
SPPrefPaneDataType
SPStartupItemDataType
SPSyncServicesDataType
SPUniversalAccessDataType
mress:10009 Z$ system_profiler SPHardwareDataType
Hardware:

    Hardware Overview:

      Model Name: iMac
      Model Identifier: iMac10,1
      Processor Name: Intel Core 2 Duo
      Processor Speed: 3.33 GHz
      Number Of Processors: 1
      Total Number Of Cores: 2
      L2 Cache: 6 MB
      Memory: 16 GB
      Bus Speed: 1.33 GHz
      Boot ROM Version: IM101.00CC.B00
      SMC Version (system): 1.52f9
      Serial Number (system): QP0241DXB9S
      Hardware UUID: 01C6B9E9-B0CB-5249-8AC7-069A3E44A188

You can also get some useful information from /usr/sbin/sysctl (try sysctl -a).

mress:10014 Z$ sudo sysctl -a | grep cache
Password:
hw.cachelinesize = 64
hw.l1icachesize = 32768
hw.l1dcachesize = 32768
hw.l2cachesize = 6291456
kern.flush_cache_on_write: 0
vfs.generic.nfs.client.access_cache_timeout: 60
vfs.generic.nfs.server.reqcache_size: 64
net.inet.ip.rtmaxcache: 128
net.inet6.ip6.rtmaxcache: 128
hw.cacheconfig: 2 1 2 0 0 0 0 0 0 0
hw.cachesize: 17179869184 32768 6291456 0 0 0 0 0 0 0
hw.cachelinesize: 64
hw.l1icachesize: 32768
hw.l1dcachesize: 32768
hw.l2cachesize: 6291456
machdep.cpu.cache.linesize: 64
machdep.cpu.cache.L2_associativity: 8
machdep.cpu.cache.size: 6144