Change backup storage free() to use pwrite().
Change backup storage free() to use pwrite().

behnamm/cs244b_project,SMatsushi/RAMCloud,IMCG/RamCloud,DavidLi2010/ramcloud,taschik/ramcloud-load-manager,utah-scs/RAMCloud,jblomer/ramcloud,jcarreira/ramcloud,rstutsman/RAMCloud,taschik/ramcloud,mrdiegoa/ramcloud,QingkaiLu/RAMCloud,Frank-Wu/RamCloud,utah-scs/RAMCloud,QingkaiLu/RAMCloud,y-higuchi/ramcloud,IMCG/RamCloud,jcarreira/ramcloud,taschik/ramcloud-load-manager,rstutsman/RAMCloud,anirajk/RAMCloud,taschik/ramcloud,matrix207/RAMCloud,behnamm/cs244b_project,behnamm/cs244b_project,taschik/ramcloud,alexandermerritt/ramcloud,alexandermerritt/ramcloud,SMatsushi/RAMCloud,DavidLi2010/ramcloud,Frank-Wu/RamCloud,SMatsushi/RAMCloud,anirajk/RAMCloud,DavidLi2010/ramcloud,Frank-Wu/RamCloud,rstutsman/RAMCloud,IMCG/RamCloud,mrdiegoa/ramcloud,SMatsushi/RAMCloud,behnamm/cs244b_project,DavidLi2010/ramcloud,IMCG/RamCloud,utah-scs/RAMCloud,QingkaiLu/RAMCloud,alexandermerritt/ramcloud,taschik/ramcloud,jcarreira/ramcloud,jblomer/ramcloud,mrdiegoa/ramcloud,y-higuchi/ramcloud,rstutsman/RAMCloud,anirajk/RAMCloud,taschik/ramcloud-load-manager,matrix207/RAMCloud,SMatsushi/RAMCloud,Frank-Wu/RamCloud,rstutsman/RAMCloud,QingkaiLu/RAMCloud,matrix207/RAMCloud,QingkaiLu/RAMCloud,QingkaiLu/RAMCloud,alexandermerritt/ramcloud,y-higuchi/ramcloud,jcarreira/ramcloud,taschik/ramcloud-load-manager,behnamm/cs244b_project,SMatsushi/RAMCloud,DavidLi2010/ramcloud,mrdiegoa/ramcloud,anirajk/RAMCloud,y-higuchi/ramcloud,alexandermerritt/ramcloud,jblomer/ramcloud,utah-scs/RAMCloud,IMCG/RamCloud,utah-scs/RAMCloud,anirajk/RAMCloud,mrdiegoa/ramcloud,utah-scs/RAMCloud,IMCG/RamCloud,mrdiegoa/ramcloud,alexandermerritt/ramcloud,jblomer/ramcloud,y-higuchi/ramcloud,Frank-Wu/RamCloud,taschik/ramcloud-load-manager,anirajk/RAMCloud,matrix207/RAMCloud,taschik/ramcloud,DavidLi2010/ramcloud,matrix207/RAMCloud,Frank-Wu/RamCloud,jcarreira/ramcloud,jblomer/ramcloud,y-higuchi/ramcloud,jcarreira/ramcloud,jblomer/ramcloud,matrix207/RAMCloud,behnamm/cs244b_project,rstutsman/RAMCloud