Differences
This shows you the differences between two versions of the page.
| Next revision | Previous revision | ||
|
soc:2010:cooldavid:notes:gpxememlayout [2010/06/02 12:45] cooldavid created |
soc:2010:cooldavid:notes:gpxememlayout [2010/06/02 13:12] (current) cooldavid |
||
|---|---|---|---|
| Line 99: | Line 99: | ||
| </file> | </file> | ||
| - | ==== Current memory usage ==== | + | ==== Memory usage ==== |
| + | We can see the current memory usage by the symbols | ||
| + | exported by linker. Which is defined in the linker | ||
| + | script mentioned in the previours section. | ||
| + | For ''i386.lds'', if we want to know how much memory | ||
| + | was used. We can simply check for _etextdata, or _stack. | ||
| + | |||
| + | The heap was declared as globle variable in ''src/core/malloc.c'', | ||
| + | which would put in bss section. We can get its address by: | ||
| + | == objdump -t bin/gpxe.pxe.tmp | grep ' heap$' == | ||
| + | <file> | ||
| + | 000b3c5c l O .bss.textdata 00020000 heap | ||
| + | </file> | ||
| + | |||
| + | As long as the _stack plus real stack usage at runtime dose | ||
| + | not exceed 1MB, we should be safe. | ||
| + | |||
| + | We can also exam the what symbol cost most memory size by: | ||
| + | == readelf -W -s bin/gpxe.pxe.tmp | sort -n -k 3 | tail == | ||
| + | <file> | ||
| + | 463: 0007c7a4 6104 OBJECT LOCAL DEFAULT 5 bnx2_rv2p_proc2 | ||
| + | 1337: 000a505c 6320 OBJECT LOCAL DEFAULT 6 rxb | ||
| + | 3869: 00091738 8192 OBJECT GLOBAL HIDDEN 5 linda_ib_fw | ||
| + | 1351: 000a6f4c 9084 OBJECT LOCAL DEFAULT 6 rx_buffer | ||
| + | 391: 00094e9c 9348 OBJECT LOCAL DEFAULT 6 amd8111e | ||
| + | 469: 00083838 22348 OBJECT LOCAL DEFAULT 5 bnx2_TXP_b06FwText | ||
| + | 479: 0008a1b4 22464 OBJECT LOCAL DEFAULT 5 bnx2_COM_b06FwText | ||
| + | 464: 0007df7c 22672 OBJECT LOCAL DEFAULT 5 bnx2_RXP_b06FwText | ||
| + | 461: 00099874 41848 OBJECT LOCAL DEFAULT 6 bnx2_bss | ||
| + | 1344: 000a92c8 43064 OBJECT LOCAL DEFAULT 6 virtqueue | ||
| + | </file> | ||
| + | The number bigger than 5 digits in decimal, were displayed as hex. | ||
| + | == readelf -W -s bin/gpxe.pxe.tmp | grep ' 0x[0-9]\+ ' == | ||
| + | <file> | ||
| + | 2052: 000b3c5c 0x20000 OBJECT LOCAL DEFAULT 6 heap | ||
| + | 3141: 000d4100 0x18808 OBJECT GLOBAL HIDDEN 6 _shared_bss | ||
| + | </file> | ||
