コマンド学習「sar」(Vol.2)
「sar -b」って何だろう?
option | desctiption |
---|---|
-b | Report I/O and transfer rate statistics. This option works only with kernels older than 2.5. |
# sar -b 1 2
Linux 2.6.9-78.0.22.EL (localhost.localdomain) 2009年08月24日16時55分22秒 tps rtps wtps bread/s bwrtn/s
16時55分23秒 0.99 0.99 0.00 7.92 0.00
16時55分24秒 0.00 0.00 0.00 0.00 0.00
平均値: 0.50 0.50 0.00 4.02 0.00
カラム名 | 詳細 | |
---|---|---|
tps | Total number of transfers per second that were issued to the physical disk. A transfer is an I/O request to the physical disk. Multiple logical requests can be combined into a single I/O request to the disk. A transfer is of indeterminate size. | |
rtps | Total number of read requests per second issued to the physical disk. | |
wtps | Total number of write requests per second issued to the physical disk. | |
bread/s | Total amount of data read from the drive in blocks per second. Blocks are equivalent to sectors with 2.4 kernels and newer and therefore have a size of 512 bytes. With older kernels, a block is of indeterminate size. | |
bwrtn/s | Total amount of data written to the drive in blocks per second. |
カラム名 | 詳細(日本語) |
---|---|
tps | 1秒あたりの物理デバイスに対するI/O要求数(サイズ不定) |
rtps | 1秒あたりの物理デバイスに出されたread要求回数 |
wtps | 1秒あたりの物理デバイスに出されたwrite要求回数 |
bread/s | 1秒あたりの物理デバイスから読み出されたデータ量(ブロック単位(=512byte)) |
bwrtn/s | 1秒あたりの物理デバイスに書き込まれたデータ量(ブロック単位(=512byte)) |