Enq: HW - contention

Question

hi
in my spreport i am getting this enq problem pls tell me how to solve this.
Top 5 Timed Events Avg %Total
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time
buffer busy waits 1,480,241 1,024,132 692 64.5
enq: HW - contention 142,929 389,756 2727 24.5
free buffer waits 5,245,113 99,454 19 6.3
enq: US - contention 12,172 19,131 1572 1.2
db file parallel write 5,228 10,397 1989 .7
log_buffer=25m
checkpointtimeout=0
checkpointinterval=0
thanks.

Answer 1

Total System Global Area 599785472 bytes
Fixed Size 1980328 bytes
Variable Size 146802776 bytes
Database Buffers 423624704 bytes
Redo Buffers 27377664 bytes
using 10gr2
simultaniously 150 user will affect the database.In this database we have create 150 tables.the procedure is.after creating this table using afterinsertion procedure to insert the data in table.We were using 150 procedure to insert 150 tables.
declare
counter NUMBER;
sql_string VARCHAR2(2000);
BEGIN FOR counter IN 1..150 LOOP
sql_string := 'CREATE TABLE emp'||counter||'
(id varchar2(10) primary key,
col_a varchar2(10),
col_b date,
col_c varchar2(10),
col_d varchar2(10),
col_e varchar2(10),
col_f varchar2(10),
col_g varchar2(10),
col_h date,
col_i varchar2(10),
col_j varchar2(10),
col_k date,
col_l varchar2(10),
col_m varchar2(10),
col_n varchar2(10),
col_o varchar2(10),
col_p varchar2(10),
col_q date,
col_r varchar2(10),
col_s varchar2(10),
col_t varchar2(10),
col_u varchar2(10),
col_v char(20),
col_w varchar2(10),
col_x date,
col_y varchar2(10),
col_z varchar2(10),
col_aa varchar2(10),
col_bb varchar2(10),
col_cc char(20),
col_dd varchar2(10),
col_ee date,
col_ff varchar2(10),
col_gg varchar2(10),
col_hh varchar2(10),
col_ii varchar2(10),
col_jj char(10),
col_kk varchar2(10),
col_ll date,
col_mm varchar2(10),
col_nn varchar2(10),
col_oo varchar2(10),
col_pp varchar2(10),
col_qq char(10),
col_rr varchar2(10),
col_ss date,
col_tt varchar2(10),
col_uu varchar2(10),
col_vv varchar2(10),
col_ww varchar2(10),
col_xx char(12)
) TABLESPACE employee
PCTFREE 10
INITRANS 10
MAXTRANS 255
STORAGE
INITIAL 50m
next 50M
MAXEXTENTS UNLIMITED
EXECUTE IMMEDIATE sql_string;
END LOOP;
END;
CREATE OR REPLACE procedure afterinsertion1(n in number)
is
a number;
cc number;
BEGIN
cc:=1;
FOR innercounter IN 1 .. n LOOP
INSERT INTO emp1(id, col_a ,col_b,col_c ,col_d ,col_e, col_f ,col_g ,col_h ,col_i ,col_j ,col_k,col_l,col_m,col_n,col_o,col_p,
col_q,col_r,col_s,col_t,col_u,col_v,col_w,col_x,col_y,col_z,col_aa,col_bb,col_cc,col_dd,col_ee,col_ff,col_gg,
col_hh,col_ii,col_jj,col_kk,col_ll,col_mm,col_nn,col_oo,col_pp,col_qq,col_rr,col_ss,col_tt,col_uu,col_vv,col_ww,
col_xx) VALUES (id.nextval,'col_a','11-JAN-07','col_c','col_d','col_e','col_f','col_g','11-JAN-07' ,'col_i' ,'col_j',
'11-JAN-07','col_l','col_m','col_n','col_o','col_p','11-JAN-07','col_r','col_s','col_t','col_u','col_v','col_w',
'11-JAN-07','col_y','col_z','col_aaa','COL_BB','col_cc','col_dd','11-JAN-07','col_ff','col_gg','col_h','col_ii','col_jj',
'col_kk','11-JAN-07','col_mm','col_nn','col_o','col_pp','col_qq','col_rr','11-JAN-07','col_tt','col_uu',
'col_v','col_ww','col_xx');
cc:=cc+1;
if cc > 3 then
     commit;
     cc:=0;
end if;
END LOOP;
END;
/