Ada 3 metode blocking :
- Fixed Blocking
Bfr = [B/R]
2. Variable - Length Spanned Blocking
Rumusnya :
3. Variable - Length Unspanned Blocking
Rumusnya :
Pemborosan Ruang
Nilai Pemborosan Ruang :
Fixed Blocking :
Variable Length Spanned Blocking :
Variable Length Unspanned Blocking :
Keterangan :
B = Block Size
P = Block Pointer
R = Panjang Record Rata - rata
M = Record Mark
= Pemborosan karena Gap
= Pemborosan karena blocking
Latihan :
- Block size (B) = 250 byte, record length (R) = 45 byte, hitung blocking factor (Bfr) !
Bfr = [B/R]
= [250/45]
Bfr = 5,5 = 5
2. Ukuran block (B) = 300 byte, block pointer (P) = 2 byte, panjang record rata-rata (R) = 60 byte, ukuran record mark (M) = 1 byte. Berapa Bfr dan Pemborosan Ruang dengan menggunakan :
a. Spanned blocking
b. Unspanned blocking
Jawab :
a. Spanned Blocking =
b. Unspanned Blocking =
Pemborosan Ruang
Fixed Blocking
= 0,8 + 4
= 4,8
Spanned Blocking
Unspanned Blocking